diff --git a/PRESUBMIT.py b/PRESUBMIT.py
index cbe2d9f..8e0ac49 100755
--- a/PRESUBMIT.py
+++ b/PRESUBMIT.py
@@ -135,8 +135,8 @@
           long_text = match.group(1).strip()
       except IOError:
         pass
-      return [output_api.PresubmitPromptWarning("The tree is closed.",
-                                                long_text=long_text)]
+      return [output_api.PresubmitError("The tree is closed.",
+                                        long_text=long_text)]
   except IOError:
     pass
   return []