diff --git a/app/controllers/submissions_controller.rb b/app/controllers/submissions_controller.rb
index 16fcd697..361ed866 100644
--- a/app/controllers/submissions_controller.rb
+++ b/app/controllers/submissions_controller.rb
@@ -173,7 +173,7 @@ class SubmissionsController < ApplicationController
 
   def handle_message(message, tubesock, container)
     # Handle special commands first
-    if (/^exit/.match(message))
+    if (/^#exit/.match(message))
       kill_socket(tubesock)
       @docker_client.exit_container(container)
     else