diff --git a/lib/file_store/local_store.rb b/lib/file_store/local_store.rb
index 5b23505998f..3e5931ae8a0 100644
--- a/lib/file_store/local_store.rb
+++ b/lib/file_store/local_store.rb
@@ -59,7 +59,7 @@ module FileStore
     end
 
     def purge_tombstone(grace_period)
-      Discourse::Utils.execute_command('find', tombstone_dir, '-mtime', "+#{grace_period}", '-type f -delete')
+      Discourse::Utils.execute_command('find', tombstone_dir, '-mtime', "+#{grace_period}", '-type', 'f', '-delete')
     end
 
     def get_path_for(type, upload_id, sha, extension)