Megadeth’s set at Metalfest Open Air Festival in Croatia was brought to a hasty finish after frontman Dave Mustaine was pelted with rocks by members of the crowd.

Mustaine pulled the plug on the show after being struck repeatedly from a barrage of beer bottles, finally departing the stage after a rock struck him in the head. The projectiles were being thrown by unruly members of the crowd who were chanting in demand for ’80s hair metal act W.A.S.P. – who had cancelled their appearance earlier in the afternoon.

Why the attack on Mustaine and his band? Because apparently he was the reason behind W.A.S.P.’s unscheduled cancellation.

According to unfounded rumours that had been circulating throughout the Croatian festival, Blackie Lawless, singer for W.A.S.P., had refused to perform at the event because of an argument with Dave Mustaine.

Metal Injection points out fans’ suggestions that the thrash metal frontman may have refused to play alongside W.A.S.P. because of his “no performance with Satanists” policy. Mustaine has previously refused to play alongside acts like Rotting Christ and Dissection, because of the satanic references in their songs.

Following his stoning at the concert, the rowdy audience began booing in earnest, chanting “we want W.A.S.P.” before a spokesman appeared on stage saying, “Guys, Dave’s been hit in the head with a rock.” His apologies were drowned out by the crowd before more items were pelted onstage.

Though Mustaine’s falling out with Lawless is unconfirmed from either party yet, the Megadeth singer isn’t known to be the most sensitive of public speakers. Earlier this year, he upset readers of LA Weekly when he remarked that Africa could solve some of their ‘problems’ if their women “put a plug in it.”

Footage of the stoning has surfaced on YouTube, and you can watch below. The crowd begins to get rowdy about 6 minutes in, the chanting begins at 8 minutes, Mustaine walks off stage about 9 1/2 minutes, and the spokesperson appears on stage at 13 minutes.