Bassist Ken Casey was bloodied after being hit in the face with a can during the Boston show.

The Dropkick Murphys are speaking out about a bloody brawl during one of their hometown St. Patrick's Day shows at Boston's House of Blues on Friday (March 15).

A rep for the band tells Billboard that the fight started after bassist and Dropkick Murphys founder Ken Casey saw an inebriated fan elbowing and hitting women near the stage. Casey reportedly stopped the show and called for security to grab the offending fan and then jumped into a barricade and started shouting for the man to stop.

A video first shared by TMZ shows Casey with blood on his face, shouting at an individual in the audience and then jumping into the crowd.

Billboard obtained a second video of the fight that shows Casey standing over the front section trying to break up the fight and then getting hit in the head with a beer can thrown from the crowd. After a brief tussle, Casey helps security bring one suspected troublemaker over the barricade, before the stage crew pull Casey away and security escorts the young man out the venue while fans jeer and cheer.

"Ken could see the guy wasn't going to stop and that security was having a hard time getting to him, so he decided to handle it himself," a source close to the band tells Billboard. "Ken is not afraid to stand up to anyone who is ruining the show for someone else and the band has been clear that they won't tolerate abusive behavior."

The Boston punk rock band is known for its raucous concerts, and while fights are rare, the Dropkick Murphys and their fans have gotten into fights with racist skinheads and Neo Nazis who have tried to disrupt their concerts. In 2013, a skinhead tried to jump on the stage during the band's show at Terminal 5 in New York.

"We've been doing this for a number of years, and having been here for 21 of those years, I can tell you this is not new," lead singer Al Barr told the audience after the fight broke up. "When we invite you guys to come to one of our shows, it's like were saying come to our house. And when someone disrespects us, you're disrespecting us in our house."

The Dropkick Murphys are currently finishing up their St. Patrick's Day tour, playing five shows in five days in Boston, including today's St. Patrick's Clash 4 featuring a performance by the band and boxing matches promoted by Murphy's Boston.

Reps for Casey say he is feeling fine and already back to performing.