TEHRAN (Reuters) - Iranian police detained more than 200 people and seized alcohol and drugs in a raid on a “satanic” underground rock concert, media in the conservative Islamic state reported on Saturday.

Iran, which has launched an annual summer crackdown on “immoral behavior”, bans alcohol, narcotics and parties with unrelated men and women dancing, drinking and mixing. Western popular music is frowned upon.

The police operation took place on Wednesday night in the town of Karaj near the capital Tehran, at an event with local disc jockeys, rock and rap groups performing, the media said.

“Most of those arrested are wealthy young people ... who came to this party with the goal of attending a provocative, satanic concert,” daily Tehran-e Emrouz quoted a senior police official, Reza Zarei, as saying.

Karaj’s public prosecutor, Ali Farhadi, said invitations had been sent out via the Internet and that people from Britain and Sweden were among those held. Zarei suggested they were expatriate Iranians visiting the country.

Farhadi said 150 bottles of alcoholic drinks, 800 “obscene” CDs and different kinds of drugs had been confiscated by police, as well as “inappropriate” dresses that those behind the event were giving to female guests as gifts.

“Some 230 people who attended a rock party in Karaj were identified and arrested,” Farhadi said on the Web site of Iran’s state broadcaster.

He said 20 video cameras had also been seized and that the organizers had planned to blackmail girls after filming “inappropriate and obscene” videos of them.

Under sharia, Islamic law, imposed after Iran’s 1979 revolution, women are obliged to cover their hair and wear long, loose clothing to disguise their figures and protect their modesty. Violators can receive lashes, fines or imprisonment.