SAMARRA, Iraq (Reuters) - A dawn bomb attack wrecked a major Shi'ite Muslim shrine in the Iraqi city of Samarra on Wednesday, sparking protests, some of them violent, and forcing an urgent government appeal to avoid sectarian reprisals.
Some Sunni mosques were damaged in revenge attacks, Shi'ite militiamen posted themselves on streets and Iraq's senior Shi'ite cleric called for peaceful protests.
The Iraqi president said the attackers wanted to derail efforts to form a national unity government. Iraq's national security adviser accused al Qaeda-inspired Sunni militants of blasting the Shi'ite shrine to foment civil war.
There was no immediate claim of responsibility.
Gunmen burst into Samarra's Golden Mosque, one of Iraq's four holiest Shi'ite sites, and used explosives to bring down its 100-year-old gilded dome, among the biggest in the Muslim world, senior officials said. No casualties were reported.
An aerial photograph released by the U.S. military showed the 20-meter (33-foot) wide dome reduced to a shell of brown masonry and twisted iron, with nearby buildings also wrecked.