You don't need a mod to do it Just make a .htaccess file and ban their IP ranges, so if you feel that your getting spammed from china, ban the country
http://www.countryipblocks.net/count...elect-formats/
Theres no real quick way to do it, any way will require some involvement from you at admin level.
There was a mod which i could remember from a few years ago call "One Touch Clean and Ban" which allowed you to ban and automatically delete all posts, But i guess if you did a search you might fine it

Not sure if it would work with the latest VB, but hey, anythings worth a try
Good luck