MANAMA, Bahrain - Religious protesters chanting "No to unclean tourism" clashed with riot police outside an exhibition center where sultry Lebanese singer Nancy Ajram was performing.

The planned protest by about 150 to 300 Shiite Muslims, including women covered from head to toe, turned chaotic Wednesday when the protesters tried to prevent concertgoers from entering the exhibition center grounds. Riot police intervened, and the protesters threw rocks, set fires and smashed car windows.

"We don't want such un-Islamic acts in our country and we'll see to it that these things are not repeated," one protester said of the concert by Ajram, who is known for provocative videos where she wears tight, revealing clothing and dances seductively.

Although an Islamic state, Bahrain has a more relaxed climate than its stricter neighbors. Earlier this week, conservative lawmakers had proposed banning the pop concert, noting that the holy month of Ramadan was about to begin, but they were rebuffed by the moderate majority.

Police said several people were arrested and at least 13 cars were damaged in the melee Wednesday.

But while the riot continued outside, inside it was a typical concert, with young men and women dancing in the aisles and singing along with Ajram, who was dressed relatively conservatively in tight jeans, a light T-shirt and a black jacket.