Kabul, Afghanistan - Hundreds of Shi'a Muslims and Sunnis clashed in a western Afghan city on Thursday during an important Shi'a festival, exchanging fire, hurling grenades and burning mosques. One doctor said at least four people had been killed and 51 injured.
A senior police officer, Ismatullah Mohammed, said Islamic extremists were suspected of having incited the violence. The fighting followed three days of rioting across Afghanistan over drawings of the Prophet Muhammad, first published in a Danish newspaper. Those riots left 11 dead.
Thursday's fighting started after 300 Sunnis threw stones at a Shi'a mosque during the sect's most important festival, Ashoura.
Such attacks are rare in Afghanistan, where there has been little tension between the two sects. The Shi'as responded, attacking Sunnis in a camp for displaced people. The violence then spread across the city with both sides throwing grenades at each other, burning about a dozen cars and two mosques.
Local resident Abdul Nafai said the police had fired into the air to try to separate the two sides, but failed. Mohammed said hundreds of young men were believed to be coming into Herat from surrounding towns and villages to join the fighting, and security forces had been ordered to block roads.