TEHRAN - A bomb blast tore through a Shi'ite Muslim house of worship in a southern Iranian city last night, killing at least nine people and injuring more than 100 others, most of them gathered to hear a religious speech about the dangers of Sunni extremists.
The explosion shattered shop windows and damaged buildings in a 1-mile area of the ancient city of Shiraz. Ambulances and firefighters rushed to the scene to rescue the wounded, who flooded city hospitals.
Witnesses said about 800 worshipers were in the mosque when the blast occurred. Many of the injured were in critical condition. Authorities set up a hot line for relatives to find out about casualties. No group immediately claimed responsibility for the attack, and Iranian authorities told news agencies that the blast remained under investigation.
The explosion occurred at a "hosseinyeh," a Shi'ite house of worship similar to a mosque but often used for community and religious activities.
Fars, a semiofficial Iranian news agency, reported that a midranking cleric identified only as Anjivinejad was delivering a speech about the "misleading and corrupted cults" of the Wahhabi Islamic school that inspires Osama bin Laden as well as the Baha'i faith, another Islamic offshoot, when the blast went off.
The cleric survived attack with slight injuries, Fars reported.
Shiraz is an old southern city that once hosted famous Persian poets. It is also the namesake of the famous wine grape. In recent weeks, the city has experienced student unrest.
Few ethnic and religious minorities live in the city. But southwestern Iran, abutting Iraq, is home to Sunni and Shi'ite Arabs who occasionally have rebelled against the rule of the Islamic Republic, which holds Shi'ite Islam as the official state religion and is dominated by ethnic Persians and Azeris.
Bombings are rare in Iran, but insurgencies have been blamed for some deadly bomb attacks in recent years. In February 2007, a car loaded with explosives blew up near a bus carrying members of Iran's Revolutionary Guard, killing 11 of them. In 2006, blasts killed nine people in Ahvaz near the Iraq border.
Iran alleges that the United States, Israel, and Britain are behind the upsurge in militant activity and says it has intelligence to support the allegation.
"There are numerous ethnic and/or religious minority groups within Iran and in neighboring countries with grievances against Iran's fundamentalist clergy," said Karim Sadjadpour, an Iran specialist at Carnegie Endowment for International Peace in Washington.