diff --git a/cpp/src/ray/runtime/task/local_mode_task_submitter.cc b/cpp/src/ray/runtime/task/local_mode_task_submitter.cc
index 3e7864f63..280a642c6 100644
--- a/cpp/src/ray/runtime/task/local_mode_task_submitter.cc
+++ b/cpp/src/ray/runtime/task/local_mode_task_submitter.cc
@@ -34,7 +34,8 @@ ObjectID LocalModeTaskSubmitter::Submit(const InvocationSpec &invocation, TaskTy
                             local_mode_ray_tuntime_.GetCurrentJobID(),
                             local_mode_ray_tuntime_.GetCurrentTaskId(), 0,
                             local_mode_ray_tuntime_.GetCurrentTaskId(), address, 1,
-                            required_resources, required_placement_resources);
+                            required_resources, required_placement_resources,
+                            PlacementGroupID::Nil());
   if (type == TaskType::NORMAL_TASK) {
   } else if (type == TaskType::ACTOR_CREATION_TASK) {
     builder.SetActorCreationTaskSpec(invocation.actor_id);
diff --git a/python/ray/state.py b/python/ray/state.py
index 1d6c44104..b2b6e5792 100644
--- a/python/ray/state.py
+++ b/python/ray/state.py
@@ -377,7 +377,6 @@ class GlobalState:
 
         return dict(result)
 
-    # SANG-TODO Add functions.
     def placement_group_table(self, placement_group_id=None):
         self._check_connected()
 
diff --git a/python/ray/tests/test_placement_group.py b/python/ray/tests/test_placement_group.py
index 1b6280556..1bb963c44 100644
--- a/python/ray/tests/test_placement_group.py
+++ b/python/ray/tests/test_placement_group.py
@@ -246,33 +246,46 @@ def test_remove_placement_group(ray_start_cluster):
     # # Now let's create a placement group.
     pid = ray.experimental.placement_group([{"CPU": 2}, {"CPU": 2}])
 
-    # # This is a hack to wait for placement group creation.
-    # # TODO(sang): Remove it when wait is implemented.
-    @ray.remote(num_cpus=0)
+    # Create an actor that occupies resources.
+    @ray.remote(num_cpus=2)
     class A:
         def f(self):
             return 3
 
+    # Currently, there's no way to prevent
+    # tasks to be retried for removed placement group.
+    # Set max_retrie=0 for testing.
+    # TODO(sang): Handle this edge case.
+    @ray.remote(num_cpus=2, max_retries=0)
+    def long_running_task():
+        print(os.getpid())
+        import time
+        time.sleep(50)
+
+    # Schedule a long running task and actor.
+    task_ref = long_running_task.options(placement_group_id=pid).remote()
     a = A.options(placement_group_id=pid).remote()
     assert ray.get(a.f.remote()) == 3
+
     ray.experimental.remove_placement_group(pid)
-    # # Subsequent remove request shouldn't do anything
+    # Subsequent remove request shouldn't do anything.
     for _ in range(3):
         ray.experimental.remove_placement_group(pid)
 
-    # # Make sure placement group resources are
-    # # released and we can schedule this task.
+    # Make sure placement group resources are
+    # released and we can schedule this task.
     @ray.remote(num_cpus=4)
     def f():
         return 3
 
     assert ray.get(f.remote()) == 3
-
     # Since the placement group is removed,
     # the actor should've been killed.
     # That means this request should fail.
-    # TODO(sang): Turn it on.
-    # ray.get(a.f.remote())
+    with pytest.raises(ray.exceptions.RayActorError, match="actor died"):
+        ray.get(a.f.remote(), timeout=3.0)
+    with pytest.raises(ray.exceptions.RayWorkerError):
+        ray.get(task_ref)
 
 
 def test_remove_pending_placement_group(ray_start_cluster):
diff --git a/src/ray/common/task/task_spec.cc b/src/ray/common/task/task_spec.cc
index e7de6cb3a..ee8785713 100644
--- a/src/ray/common/task/task_spec.cc
+++ b/src/ray/common/task/task_spec.cc
@@ -43,6 +43,10 @@ SchedulingClass TaskSpecification::GetSchedulingClass(const ResourceSet &sched_c
   return sched_cls_id;
 }
 
+const PlacementGroupID TaskSpecification::PlacementGroupId() const {
+  return PlacementGroupID::FromBinary(message_->placement_group_id());
+}
+
 void TaskSpecification::ComputeResources() {
   auto required_resources = MapFromProtobuf(message_->required_resources());
   auto required_placement_resources =
diff --git a/src/ray/common/task/task_spec.h b/src/ray/common/task/task_spec.h
index 8e963f433..e300c7624 100644
--- a/src/ray/common/task/task_spec.h
+++ b/src/ray/common/task/task_spec.h
@@ -189,6 +189,9 @@ class TaskSpecification : public MessageWrapper<rpc::TaskSpec> {
   // Compute a static key that represents the given resource shape.
   static SchedulingClass GetSchedulingClass(const ResourceSet &sched_cls);
 
+  // Placement Group ID that this task or actor creation is associated with.
+  const PlacementGroupID PlacementGroupId() const;
+
  private:
   void ComputeResources();
 
diff --git a/src/ray/common/task/task_util.h b/src/ray/common/task/task_util.h
index c562d6d25..c0670fd2b 100644
--- a/src/ray/common/task/task_util.h
+++ b/src/ray/common/task/task_util.h
@@ -85,7 +85,8 @@ class TaskSpecBuilder {
       const TaskID &parent_task_id, uint64_t parent_counter, const TaskID &caller_id,
       const rpc::Address &caller_address, uint64_t num_returns,
       const std::unordered_map<std::string, double> &required_resources,
-      const std::unordered_map<std::string, double> &required_placement_resources) {
+      const std::unordered_map<std::string, double> &required_placement_resources,
+      const PlacementGroupID &placement_group_id) {
     message_->set_type(TaskType::NORMAL_TASK);
     message_->set_language(language);
     *message_->mutable_function_descriptor() = function_descriptor->GetMessage();
@@ -100,6 +101,7 @@ class TaskSpecBuilder {
                                                    required_resources.end());
     message_->mutable_required_placement_resources()->insert(
         required_placement_resources.begin(), required_placement_resources.end());
+    message_->set_placement_group_id(placement_group_id.Binary());
     return *this;
   }
 
diff --git a/src/ray/core_worker/core_worker.cc b/src/ray/core_worker/core_worker.cc
index 2f8dd59a5..48282e486 100644
--- a/src/ray/core_worker/core_worker.cc
+++ b/src/ray/core_worker/core_worker.cc
@@ -37,12 +37,12 @@ void BuildCommonTaskSpec(
     const std::vector<std::unique_ptr<ray::TaskArg>> &args, uint64_t num_returns,
     const std::unordered_map<std::string, double> &required_resources,
     const std::unordered_map<std::string, double> &required_placement_resources,
-    std::vector<ObjectID> *return_ids) {
+    std::vector<ObjectID> *return_ids, const ray::PlacementGroupID &placement_group_id) {
   // Build common task spec.
-  builder.SetCommonTaskSpec(task_id, function.GetLanguage(),
-                            function.GetFunctionDescriptor(), job_id, current_task_id,
-                            task_index, caller_id, address, num_returns,
-                            required_resources, required_placement_resources);
+  builder.SetCommonTaskSpec(
+      task_id, function.GetLanguage(), function.GetFunctionDescriptor(), job_id,
+      current_task_id, task_index, caller_id, address, num_returns, required_resources,
+      required_placement_resources, placement_group_id);
   // Set task arguments.
   for (const auto &arg : args) {
     builder.AddArg(*arg);
@@ -1222,7 +1222,8 @@ void CoreWorker::SubmitTask(const RayFunction &function,
   BuildCommonTaskSpec(builder, worker_context_.GetCurrentJobID(), task_id,
                       worker_context_.GetCurrentTaskID(), next_task_index, GetCallerId(),
                       rpc_address_, function, args, task_options.num_returns,
-                      constrained_resources, required_resources, return_ids);
+                      constrained_resources, required_resources, return_ids,
+                      placement_options.first);
   TaskSpecification task_spec = builder.Build();
   if (options_.is_local_mode) {
     ExecuteTaskLocalMode(task_spec);
@@ -1262,7 +1263,8 @@ Status CoreWorker::CreateActor(const RayFunction &function,
   BuildCommonTaskSpec(builder, job_id, actor_creation_task_id,
                       worker_context_.GetCurrentTaskID(), next_task_index, GetCallerId(),
                       rpc_address_, function, args, 1, new_resource,
-                      new_placement_resources, &return_ids);
+                      new_placement_resources, &return_ids,
+                      actor_creation_options.placement_options.first);
   builder.SetActorCreationTaskSpec(
       actor_id, actor_creation_options.max_restarts,
       actor_creation_options.dynamic_worker_options,
@@ -1363,7 +1365,7 @@ void CoreWorker::SubmitActorTask(const ActorID &actor_id, const RayFunction &fun
   BuildCommonTaskSpec(builder, actor_handle->CreationJobID(), actor_task_id,
                       worker_context_.GetCurrentTaskID(), next_task_index, GetCallerId(),
                       rpc_address_, function, args, num_returns, task_options.resources,
-                      required_resources, return_ids);
+                      required_resources, return_ids, PlacementGroupID::Nil());
 
   const ObjectID new_cursor = return_ids->back();
   actor_handle->SetActorTaskSpec(builder, new_cursor);
diff --git a/src/ray/core_worker/test/core_worker_test.cc b/src/ray/core_worker/test/core_worker_test.cc
index af87dd5ef..f28c5c486 100644
--- a/src/ray/core_worker/test/core_worker_test.cc
+++ b/src/ray/core_worker/test/core_worker_test.cc
@@ -546,7 +546,8 @@ TEST_F(ZeroNodeTest, TestTaskSpecPerf) {
     TaskSpecBuilder builder;
     builder.SetCommonTaskSpec(RandomTaskId(), function.GetLanguage(),
                               function.GetFunctionDescriptor(), job_id, RandomTaskId(), 0,
-                              RandomTaskId(), address, num_returns, resources, resources);
+                              RandomTaskId(), address, num_returns, resources, resources,
+                              PlacementGroupID::Nil());
     // Set task arguments.
     for (const auto &arg : args) {
       builder.AddArg(*arg);
diff --git a/src/ray/core_worker/test/direct_task_transport_test.cc b/src/ray/core_worker/test/direct_task_transport_test.cc
index 3f36170ad..6d2ad0444 100644
--- a/src/ray/core_worker/test/direct_task_transport_test.cc
+++ b/src/ray/core_worker/test/direct_task_transport_test.cc
@@ -326,7 +326,7 @@ TaskSpecification BuildTaskSpec(const std::unordered_map<std::string, double> &r
   rpc::Address empty_address;
   builder.SetCommonTaskSpec(TaskID::Nil(), Language::PYTHON, function_descriptor,
                             JobID::Nil(), TaskID::Nil(), 0, TaskID::Nil(), empty_address,
-                            1, resources, resources);
+                            1, resources, resources, PlacementGroupID::Nil());
   return builder.Build();
 }
 
diff --git a/src/ray/gcs/test/gcs_test_util.h b/src/ray/gcs/test/gcs_test_util.h
index 467321b0e..eaa97a1ca 100644
--- a/src/ray/gcs/test/gcs_test_util.h
+++ b/src/ray/gcs/test/gcs_test_util.h
@@ -40,7 +40,7 @@ struct Mocker {
     auto resource = std::unordered_map<std::string, double>();
     builder.SetCommonTaskSpec(task_id, Language::PYTHON, empty_descriptor, job_id,
                               TaskID::Nil(), 0, TaskID::Nil(), owner_address, 1, resource,
-                              resource);
+                              resource, PlacementGroupID::Nil());
     builder.SetActorCreationTaskSpec(actor_id, max_restarts, {}, 1, detached, name);
     return builder.Build();
   }
diff --git a/src/ray/protobuf/common.proto b/src/ray/protobuf/common.proto
index b776ec5ef..6c449275e 100644
--- a/src/ray/protobuf/common.proto
+++ b/src/ray/protobuf/common.proto
@@ -137,6 +137,8 @@ message TaskSpec {
   ActorTaskSpec actor_task_spec = 15;
   // Number of times this task may be retried on worker failure.
   int32 max_retries = 16;
+  // Placement group that is associated with this task.
+  bytes placement_group_id = 17;
 }
 
 message Bundle {
diff --git a/src/ray/raylet/node_manager.cc b/src/ray/raylet/node_manager.cc
index 2001a310b..55917b457 100644
--- a/src/ray/raylet/node_manager.cc
+++ b/src/ray/raylet/node_manager.cc
@@ -1843,11 +1843,33 @@ void NodeManager::HandleCancelResourceReserve(
     rpc::CancelResourceReserveReply *reply, rpc::SendReplyCallback send_reply_callback) {
   RAY_CHECK(!new_scheduler_enabled_) << "Not implemented";
   auto bundle_spec = BundleSpecification(request.bundle_spec());
-  RAY_LOG(DEBUG) << "bundle return resource request " << bundle_spec.BundleId().first
-                 << bundle_spec.BundleId().second;
+  RAY_LOG(INFO) << "bundle return resource request " << bundle_spec.BundleId().first
+                << bundle_spec.BundleId().second;
   auto resource_set = bundle_spec.GetRequiredResources();
-  // TODO(ekl) doesn't this not return in-use resources? We need to be able to
-  // reclaim those somehow (i.e., destroy the workers allocated in the bundle).
+
+  // Kill all workers that are currently associated with the placement group.
+  std::vector<std::shared_ptr<WorkerInterface>> workers_associated_with_pg;
+  for (const auto &worker_it : leased_workers_) {
+    auto &worker = worker_it.second;
+    if (worker->GetPlacementGroupId() == bundle_spec.PlacementGroupId()) {
+      workers_associated_with_pg.push_back(worker);
+    }
+  }
+  for (const auto &worker : workers_associated_with_pg) {
+    RAY_LOG(DEBUG)
+        << "Destroying worker since its placement group was removed. Placement group id: "
+        << worker->GetPlacementGroupId()
+        << ", bundle index: " << bundle_spec.BundleId().second
+        << ", task id: " << worker->GetAssignedTaskId()
+        << ", actor id: " << worker->GetActorId()
+        << ", worker id: " << worker->WorkerId();
+    // We should disconnect the client first. Otherwise, we'll remove bundle resources
+    // before actual resources are returned. Subsequent disconnect request that comes
+    // due to worker dead will be ignored.
+    ProcessDisconnectClientMessage(worker->Connection(), /* intentional exit */ true);
+    worker->MarkDead();
+    KillWorker(worker);
+  }
   for (auto resource : resource_set.GetResourceMap()) {
     local_available_resources_.ReturnBundleResources(bundle_spec.PlacementGroupId(),
                                                      bundle_spec.Index(), resource.first);
@@ -2507,6 +2529,7 @@ void NodeManager::AssignTask(const std::shared_ptr<WorkerInterface> &worker,
   if (task.GetTaskSpecification().IsDetachedActor()) {
     worker->MarkDetachedActor();
   }
+  worker->SetPlacementGroupId(spec.PlacementGroupId());
 
   const auto owner_worker_id = WorkerID::FromBinary(spec.CallerAddress().worker_id());
   const auto owner_node_id = ClientID::FromBinary(spec.CallerAddress().raylet_id());
diff --git a/src/ray/raylet/scheduling/cluster_task_manager_test.cc b/src/ray/raylet/scheduling/cluster_task_manager_test.cc
index 27dbd5b24..031cfa335 100644
--- a/src/ray/raylet/scheduling/cluster_task_manager_test.cc
+++ b/src/ray/raylet/scheduling/cluster_task_manager_test.cc
@@ -207,6 +207,15 @@ class MockWorker : public WorkerInterface {
     RAY_CHECK(false) << "Method unused";
   }
 
+  const PlacementGroupID &GetPlacementGroupId() const {
+    RAY_CHECK(false) << "Method unused";
+    return PlacementGroupID::Nil();
+  }
+
+  void SetPlacementGroupId(const PlacementGroupID &placement_group_id) {
+    RAY_CHECK(false) << "Method unused";
+  }
+
   std::vector<double> &GetBorrowedCPUInstances() {
     RAY_CHECK(false) << "Method unused";
     auto *t = new std::vector<double>();
@@ -258,9 +267,10 @@ Task CreateTask(const std::unordered_map<std::string, double> &required_resource
   TaskID id = RandomTaskId();
   JobID job_id = RandomJobId();
   rpc::Address address;
-  spec_builder.SetCommonTaskSpec(
-      id, Language::PYTHON, FunctionDescriptorBuilder::BuildPython("", "", "", ""),
-      job_id, TaskID::Nil(), 0, TaskID::Nil(), address, 0, required_resources, {});
+  spec_builder.SetCommonTaskSpec(id, Language::PYTHON,
+                                 FunctionDescriptorBuilder::BuildPython("", "", "", ""),
+                                 job_id, TaskID::Nil(), 0, TaskID::Nil(), address, 0,
+                                 required_resources, {}, PlacementGroupID::Nil());
 
   for (int i = 0; i < num_args; i++) {
     ObjectID put_id = ObjectID::ForPut(TaskID::Nil(), /*index=*/i + 1);
diff --git a/src/ray/raylet/task_dependency_manager_test.cc b/src/ray/raylet/task_dependency_manager_test.cc
index a4e9fa1fa..213c96732 100644
--- a/src/ray/raylet/task_dependency_manager_test.cc
+++ b/src/ray/raylet/task_dependency_manager_test.cc
@@ -112,7 +112,7 @@ static inline Task ExampleTask(const std::vector<ObjectID> &arguments,
   builder.SetCommonTaskSpec(RandomTaskId(), Language::PYTHON,
                             FunctionDescriptorBuilder::BuildPython("", "", "", ""),
                             JobID::Nil(), RandomTaskId(), 0, RandomTaskId(), address,
-                            num_returns, {}, {});
+                            num_returns, {}, {}, PlacementGroupID::Nil());
   builder.SetActorCreationTaskSpec(ActorID::Nil(), 1, {}, 1, false, "", false);
   for (const auto &arg : arguments) {
     builder.AddArg(TaskArgByReference(arg, rpc::Address()));
diff --git a/src/ray/raylet/worker.cc b/src/ray/raylet/worker.cc
index d062f49ff..4ddc252bb 100644
--- a/src/ray/raylet/worker.cc
+++ b/src/ray/raylet/worker.cc
@@ -37,6 +37,7 @@ Worker::Worker(const WorkerID &worker_id, const Language &language,
       assigned_port_(-1),
       port_(-1),
       connection_(connection),
+      placement_group_id_(PlacementGroupID::Nil()),
       dead_(false),
       blocked_(false),
       client_call_manager_(client_call_manager),
@@ -190,6 +191,14 @@ void Worker::DirectActorCallArgWaitComplete(int64_t tag) {
       });
 }
 
+const PlacementGroupID &Worker::GetPlacementGroupId() const {
+  return placement_group_id_;
+}
+
+void Worker::SetPlacementGroupId(const PlacementGroupID &placement_group_id) {
+  placement_group_id_ = placement_group_id;
+}
+
 }  // namespace raylet
 
 }  // end namespace ray
diff --git a/src/ray/raylet/worker.h b/src/ray/raylet/worker.h
index 61d811d4f..856991e86 100644
--- a/src/ray/raylet/worker.h
+++ b/src/ray/raylet/worker.h
@@ -82,6 +82,9 @@ class WorkerInterface {
 
   virtual void DirectActorCallArgWaitComplete(int64_t tag) = 0;
 
+  virtual const PlacementGroupID &GetPlacementGroupId() const = 0;
+  virtual void SetPlacementGroupId(const PlacementGroupID &placement_group_id) = 0;
+
   // Setter, geter, and clear methods  for allocated_instances_.
   virtual void SetAllocatedInstances(
       std::shared_ptr<TaskResourceInstances> &allocated_instances) = 0;
@@ -168,6 +171,9 @@ class Worker : public WorkerInterface {
 
   void DirectActorCallArgWaitComplete(int64_t tag);
 
+  const PlacementGroupID &GetPlacementGroupId() const;
+  void SetPlacementGroupId(const PlacementGroupID &placement_group_id);
+
   // Setter, geter, and clear methods  for allocated_instances_.
   void SetAllocatedInstances(
       std::shared_ptr<TaskResourceInstances> &allocated_instances) {
@@ -236,6 +242,9 @@ class Worker : public WorkerInterface {
   JobID assigned_job_id_;
   /// The worker's actor ID. If this is nil, then the worker is not an actor.
   ActorID actor_id_;
+  /// The worker's placement group ID. It is used to detect if the worker is
+  /// associated with a placement group.
+  PlacementGroupID placement_group_id_;
   /// Whether the worker is dead.
   bool dead_;
   /// Whether the worker is blocked. Workers become blocked in a `ray.get`, if