diff --git a/ospf6d/ospf6_interface.c b/ospf6d/ospf6_interface.c
index 8d42764..b0f1119 100644
--- a/ospf6d/ospf6_interface.c
+++ b/ospf6d/ospf6_interface.c
@@ -683,7 +683,7 @@
 
   /* Schedule Hello */
   if (! CHECK_FLAG (oi->flag, OSPF6_INTERFACE_PASSIVE))
-    thread_add_event (master, ospf6_hello_send, oi, 0);
+    oi->thread_send_hello = thread_add_event (master, ospf6_hello_send, oi, 0);
 
   /* decide next interface state */
   if ((if_is_pointopoint (oi->interface)) ||
@@ -771,6 +771,9 @@
     zlog_debug ("Interface Event %s: [InterfaceDown]",
 		oi->interface->name);
 
+  /* Stop Hellos */
+  THREAD_OFF (oi->thread_send_hello);
+
   /* Leave AllSPFRouters */
   if (oi->state > OSPF6_INTERFACE_DOWN)
     ospf6_sso (oi->interface->ifindex, &allspfrouters6, IPV6_LEAVE_GROUP);