diff --git a/tests/commands/create_bucket.sh b/tests/commands/create_bucket.sh
index 43d8509..1b15d99 100644
--- a/tests/commands/create_bucket.sh
+++ b/tests/commands/create_bucket.sh
@@ -26,7 +26,7 @@ create_bucket() {
   fi
 
   local exit_code=0
-  local error
+  local error error_string
   if [[ $1 == 's3' ]]; then
     error=$(send_command aws --no-verify-ssl s3 mb s3://"$2" 2>&1) || exit_code=$?
   elif [[ $1 == 's3api' ]]; then