diff --git a/endpoints/registry.py b/endpoints/registry.py
index f650398ec..bd78e6055 100644
--- a/endpoints/registry.py
+++ b/endpoints/registry.py
@@ -412,6 +412,11 @@ def put_image_json(namespace, repository, image_id):
 
   profile.debug('Looking up repo image')
   repo_image = model.get_repo_image(namespace, repository, image_id)
+  if not repo_image:
+    profile.debug('Image not found')
+    abort(404, 'Image %(image_id)s not found', issue='unknown-image',
+          image_id=image_id)
+
   uuid = repo_image.storage.uuid
 
   if image_id != data['id']: