A curtain caught fire at the American Airlines Center, sending fans to the exits but causing no injuries, KXAS-TV in Dallas reported Saturday.
The blaze was out by the time firefighters arrived, but some fans said they wanted their money back, KXAS said.
Fans told WFAA-TV in Dallas-Fort Worth that Rihanna hustled off stage as stage hands tackled the flames with a fire extinguisher.
Rihanna was a trooper after the disruption. She fired off Twitter tweets joking about setting the stage on fire and expressing disappointment and disappointing her customers.
"Glad u guys are safe!!! I promise I'll be back!!!" the pop princess said. "Heading into a production meeting to find out exactly what happened!!! Keep u posted."