Updated

A former member of the hard-core punk band the Cro-Mags attacked two of the group’s current members with a hunting knife in a dressing room before a show at Webster Hall yesterday — biting one and slashing both.

The band was about to take the stage about 8:15 p.m. when tattooed rocker Harley Flanagan, 42, barreled through the East Village venue’s VIP section toward the Cro-Mags’ dressing room, sending nearly 30 guests on the balcony into a frenzy, law enforcement sources and witnesses said.

“Someone was yelling, ‘Get his hands, get his hands, he’s got a knife!’ ” witness Dave Gustav said. “Everything went nuts.”

Several beefy security guards rushed to contain Flanagan, who seemed about to boil over before he entered the East Village venue.

“I talked to him outside minutes before it happened and I knew something was going to go down,” a witness said, according to the Horns Up Rocks website. “He was like a lunatic outside. Next thing I know he’s in the VIP area stabbing people!”

Flanagan, the band’s former bassist and founder, suffered a broken leg by the time security finally pinned him down, witnesses said. Cops handcuffed him to a chair and took him out.

“People started booing him and throwing stuff at him,” eyewitness Justin Brannan said. “His hands were handcuffed but he still gave everyone the finger.”

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