Courthouse News reports that a man who worked as stage manager for the FADER Fort party at the 2011 South By Southwest Music Festival is suing members of the Harlem-based A$AP Mob on claims that the crew beat him up as he attempted to remove sound equipment that they were breaking.

Anthony Montalbano claims that during their performance at the event, several group members “shouted obscenities indicating their dissatisfaction with the microphones and damaged musical instruments and equipment that was on the stage,” prompting a FADER employee to instruct Montalbano to go on stage and stop them.

“Plaintiff was then grabbed by the defendants and continuously punched in the face and head for several minutes and said defendants hit plaintiff in the head with a microphone,” according to Montalbano’s complaint. “Plaintiff was covered in blood and sustained serious and lasting injuries, including but not limited to an open scalp wound, concussion, abrasions, lacerations and pain in his head, neck, back, knees and ribs.”

Montalbano says he required 10 stitches in his scalp and that three A$AP Mob members were charged with assault.

Seven members of the crew are named as defendants, as are Sony Music Entertainment and Fader Media Network. Montalbano is seeking punitive and compensatory damages for negligent hiring, emotional distress, assault and battery and negligence.

Neither the A$AP Mob, Sony Music Entertainment nor Fader Media Network has responded to Montalbano’s allegations.

If Montalbano’s claims are true, it wouldn’t be the first instance of violence attributed to the A$AP Mob.

During an A$AP Rocky show at London’s Electric Ballroom last month, members of the group attacked and beat an audience member who had taken a $15,000 Rolex from Rocky’s wrist while he performed. Footage of the fracas was widely circulated on the internet.

Rocky, the group’s frontman, explained the incident during an interview shortly thereafter:

“Basically, in London some fuckin’ lil’ wise guy or thievin’-ass kid — I don’t even know how he look — decided to snatch and try to run off with my watch. … I get back on stage and next thing I know, Trapstar my security and [group member A$AP] Twelvy was beatin’ the kid up and got my watch back.”