A powerful bomb exploded inside an ancient mosque in western Afghanistan yesterday, killing at least eight people including an exiled Iranian cleric and injuring scores more, a Taliban official said.

Maulvi Mohammed Mussa, a Sunni Muslim cleric, was killed in the explosion in Herat city, along with another Iranian believed to be the bomber, Herat Provincial Governor Khairullah Kaikhwa said in a telephone interview.

Mussa had been living in Herat for several years, reportedly since his mosque in majority Shiite Muslim Iran was burned down. It was not clear whether Mussa was the target of the bombing.

Riots followed the deadly bombing, resulting in attacks on the Iranian Consulate as well as on several Shiite Muslim mosques in the city, said Khaikhwa.

The bomb exploded during afternoon prayers yesterday.

At least eight people were killed,

said Khaikhwa, but Iranian sources reached in neighboring Pakistan said the death toll was at least 20. They also said about 100 people were injured in the powerful blast.

Another Taliban official, Abdul Hanan Himat, chief of the Taliban's Bakhtar News Agency in the Afghan capital of Kabul, said that the bomb exploded inside the grand marble Jami Mosque as Mussa gave a sermon. Two of his bodyguards were among the dead.

"The people of Herat accused Iran behind this explosion is Iran," said Himat.

Immediately after the explosion hundreds of people set fire to Shiite Muslim Mosques in Herat and marched on the Iranian Consulate, destroying several vehicles and part of the consulate.

The Taliban evacuated the consulate, according to Himat, who did not know how many Iranian diplomats were at the consulate.