The Kings of Leon ended their Dallas show early on Friday night, after lead singer Caleb Followill left the stage in the middle of a song.
"I'm gonna go backstage and I'm gonna vomit, I'm gonna drink a beer and I'm gonna come back out and play three more songs," he told the crowd, before disappearing backstage.
Followill did not return to the show, and left it to his band mates to apologize to the Dallas crowd that was standing in temperatures that reached the high-90s, according to E! Online.
"Caleb's just a little unfit to maybe play the rest of the show," the remaining members said. "We're really really sorry guys . . . It's really not our fault, it's Caleb. He can't play the rest of the show."
In a statement released on Saturday, the band claimed that the Kings of Leon front man "suffered from heat exhaustion and dehydration."
The Nashville-based band went on to cancel a show in Houston, which was supposed to take place on Saturday.
Now there is speculation around possible band problems, following a Twitter rant from Followill's band mate and brother, Jared.
"Dallas, I cannot begin to tell you how sorry I am. There are internal sicknesses & problems that have needed to be addressed. No words," Jared Followill wrote on Friday following the incomplete show.
Hours later, the bassist took to Twitter again.
"I love our fans so much. I know you guys aren't stupid. I can't lie. There are problems in our band bigger than not drinking enough Gatorade," he wrote.
A show has been rescheduled for Sept. 22 in Texas.