Somebody got stabbed at the Tenacious D show. It sounds like it could be a lyric to one of the comedic-rock act’s songs, but it’s not. It happened—a few feet from where I was standing last night at the House of Blues.

Jack Black, Kyle Gass and their three-piece backing band were about 15 minutes into a headlining set when I felt a fight break out in the tightly packed crowd—between the stage-left-side bar on the venue’s downstairs level and the short staircase to the floor.

Ten or 15 seconds of pushing and shoving involving a dozen or so men ensued, and then it was over. Security stepped in and pulled a couple guys out of the melee, and it seemed like a relative non-incident … until I saw the blood. A few fairly sizable pools of it had been left behind on the wooden floor, quite the contrast to the silliness onstage, at least for those of us near enough to know something serious had just happened. Most of the crowd was blissfully unaware.

Several minutes later, Metro police arrived and roped off the area. Some of us were escorted upstairs, since our previous vantage point was now a crime scene. And, 40 minutes after the incident, Black made this announcement: “This is no joke. Due to a serious situation we’re shutting it down. We can only play one more song, but we’re gonna rock it out.” Tenacious D played “Tribute” off its first album and exited the stage an hour into the truncated set. The lights went on at 10:05, and the crowd began filing out. Before long, signs went up on the HOB box office windows announcing the cancellation of Saturday’s scheduled late-night Steel Panther show.

A few details have emerged since. One man was reportedly stabbed in the leg and is expected to recover. Another man is reportedly in custody. A House of Blues representative says the venue is "cooperating with the Las Vegas Police Department with their investigation."

What would drive someone to stab another during a performance specifically designed to make people laugh? Who can know? I do know I, for one, was (metal-detector) wanded on my way in. I can also guess security at House of Blues—and, potentially, elsewhere on the Strip—will ramp up in the aftermath. Maybe that’s not such a bad thing.