diff --git a/tsfresh/feature_extraction/extraction.py b/tsfresh/feature_extraction/extraction.py
index <HASH>..<HASH> 100644
--- a/tsfresh/feature_extraction/extraction.py
+++ b/tsfresh/feature_extraction/extraction.py
@@ -104,7 +104,7 @@ def extract_features(timeseries_container, feature_extraction_settings=None,
                                 sorting=feature_extraction_settings.PROFILING_SORTING)
 
     pool.close()
-    pool.terminate()
+    pool.join()
 
     return result
 
diff --git a/tsfresh/feature_selection/feature_selector.py b/tsfresh/feature_selection/feature_selector.py
index <HASH>..<HASH> 100644
--- a/tsfresh/feature_selection/feature_selector.py
+++ b/tsfresh/feature_selection/feature_selector.py
@@ -120,7 +120,7 @@ def check_fs_sig_bh(X, y, settings=None):
     df_features.update(p_values_of_features)
 
     pool.close()
-    pool.terminate()
+    pool.join()
 
     # Perform the real feature rejection
     if "const" in set(df_features.type):
Wait for the worker processes to exit (#<I>)

This fixes Issue #<I>