Los Angeles — Horrific video from Oct. 5 shows another 7-Eleven being violently looted by a "flash mob." The lone staffer at this location tried desperately to shut the doors before he was threatened with a concrete slab by one of the masked rioters.

Once inside, the mob attacked the clerk and looted the store. Over a dozen 7-Eleven stores have been targeted by "flash mob" robberies across Los Angeles in recent months.

Clarification: The above mob robbery at 7-Eleven occurred just outside L.A. in Anaheim, Orange County at 550 South Knott Avenue early on Oct. 6. No arrests have yet been made.