Can't resist... Rectum? Darn near killed him!

An inmate at an El Salvador jail was caught with a hand grenade stuffed up his backside -- a novel attempt to disguise his apparent escape plans.

Guards at the San Francisco Gotera prison outside the capital San Salvador found the V40 grenade, about the size of a golf ball, lodged up the man's rectum during a security clampdown, a prison spokesman said on Thursday.

They also caught another 16 inmates who each swallowed a mobile phone.