US rock singer Linda Ronstadt has been fired by the Aladdin hotel-casino in Las Vegas after she praised anti-war filmmaker Michael Moore and his new movie "Fahrenheit 9/11," the hotel said Monday.

Ronstadt, 58, called Moore a "great American patriot" who tells the truth. She also encouraged the audience to see the documentary before performing Saturday night at Aladdin hotel-casino.

But her comments drew loud boos and some of the 4,500 audience left the show to protest. People also tore down concert posters and tossed cocktails into the air, said Aladdin President Bill Timmins.

Timmins said he decided to fire Ronstadt immediately and she was escorted off the property. Ronstadt's acts "spoiled a wonderful evening for our guests and we had to do something about it," Timmins said.

Ronstadt had been booked to play the Aladdin for only one show. In an interview with the Las Vegas Review-Journal before the show, Ronstadt said "I keep hoping that if I'm annoying enough to them, they won't hire me back."