A packed Tenacious D concert at the Mandalay Bay House of Blues in Las Vegas over the weekend had to be shut down after a bloody knife fight in the crowd turned the main floor into a crime scene.

According to the Las Vegas Weekly, the rock-comedy duo of Jack Black and Kyle Gass and their 3-piece backing back were performing when a fight broke out in the audience not far from the stage. Once security had quelled the situation, “sizable pools” of blood stains were left on the venue floor from one person being stabbed in the leg during the melee.

“This is no joke. Due to a serious situation we’re shutting it down,” Jack Black announced from the stage after police had roped off the area where the stabbing occurred. “We can only play one more song, but we’re gonna rock it out,” Black added as the band played the song “Tribute” before ending the abbreviated set. A Steel Panther show scheduled for the venue later on that night was also canceled.

The victim of the stabbing was taken to a local hospital, and police have a suspect in custody.

–Scott T. Sterling, CBS Local