How to abort a clone procedure in process?

I started a site clone, and all is good except the media transfer step is taking forever - there are ~2,000 images, and the plugin seems to want to log out each, one by one, and it takes almost a minute per image.

Is there a way to cancel a Clone? Deactivating/reactivating the plugin doesn't do it. What DB tables does Cloner use to keep track of where it is in the cloning process?