diff --git a/apps/grouphandler/src/main/java/org/onosproject/grouphandler/DefaultTransitGroupHandler.java b/apps/grouphandler/src/main/java/org/onosproject/grouphandler/DefaultTransitGroupHandler.java
index 1b5bb50..b820b09 100644
--- a/apps/grouphandler/src/main/java/org/onosproject/grouphandler/DefaultTransitGroupHandler.java
+++ b/apps/grouphandler/src/main/java/org/onosproject/grouphandler/DefaultTransitGroupHandler.java
@@ -138,7 +138,8 @@
                                             Set<DeviceId> updatedNeighbors) {
         Set<Set<DeviceId>> powerSet = getPowerSetOfNeighbors(updatedNeighbors);
 
-        Set<DeviceId> tmp = updatedNeighbors;
+        Set<DeviceId> tmp = new HashSet<DeviceId>();
+        tmp.addAll(updatedNeighbors);
         tmp.remove(impactedNeighbor);
         Set<Set<DeviceId>> tmpPowerSet = getPowerSetOfNeighbors(tmp);