Shiite and Sunni leaders called for restraint, fearful that the attack would unleash a wave of sectarian violence like the one that left hundreds dead after the bombing of a revered Shiite shrine in February.
The attack came as the U.S. ambassador to Iraq, Zalmay Khalilzad, said in an interview with the BBC that, if a unified government is not formed soon, a sectarian war could erupt in Iraq and that such a war could engulf the entire Middle East.
The explosions at the historic Baratha Mosque in northern Baghdad took place right after a prominent cleric, Sheik Jalaladin al-Sagheir, delivered a searing speech demanding that the incumbent prime minister step down.
The blasts scattered bodies across the courtyard, decimated stalls of vendors selling religious texts and ripped turquoise tile from the walls. The mosque loudspeaker blared a message urging people to donate blood, while police commandos piled charred bodies into pickup trucks. A white blanket covering one body was so soaked with blood that someone tossed a black cloth over it.
People sifted through pools of blood and filled wheelbarrows with shoes and body parts.
A guard said the first bomber, a woman in black robes, had detonated her explosives at the outer gate. Panic erupted then, he said, and worshippers who had been trying to leave streamed back toward the main courtyard. Two other bombers slipped in during the chaos and detonated their explosives near the separate prayer areas for men and women, mosque and security officials said.
The well-guarded Baratha Mosque is the main religious stronghold of the Supreme Council for the Islamic Revolution, an Iranian-backed party that heads Parliament's major Shiite political bloc.
It was clear that the explosions went to the very heart of the Shiites' feeling that they are victims, as had scores of other attacks in the past three years of civil strife. On Thursday, a car bomb exploded just hundreds of yards from the golden-domed Imam Ali mosque in Najaf, killing at least 10 people in an apparent attempt to provoke a bloody cycle of reprisals.
''The Shia are being targeted in this dirty sectarian war,'' al-Sagheir said in a telephone interview with the Al Arabiya network. ''The world is watching as if what is happening means nothing.''
The sheik said there were reports that one of the bombers had been trying to make his way to the cleric's office before detonating himself.
In his Friday prayer speech, the white-turbaned sheik had called for the prime minister, Ibrahim al-Jaafari, to withdraw his bid to hold on to his job in the next government. ''There are rules in the political game, and he who can't read them will lose,'' al-Sagheir said.
Last Sunday, the sheik said in a telephone interview that al-Jaafari should abdicate to break the deadlock in forming a new government, a demand that fractured the religious Shiite bloc, which dominates the parliament.
Al-Sagheir's party, the Supreme Council, is offering one of its deputies, Vice President Adel Abdul Mahdi, as the new nominee for prime minister. Abdul Mahdi lost to al-Jaafari by one vote in a secret ballot in February among the 130 members of the Shiite bloc. Al-Jaafari has the backing of Muqtada al-Sadr, the rebellious cleric who despises the Supreme Council.
Both al-Sadr and the Supreme Council have formidable militias that have clashed in open street battles.
But the mosque attack appeared to be the work of jihadists aligned with the Sunni-led insurgency rather than violence between Shiites.
In his BBC interview, Khalilzad again emphasized the need for Iraqi leaders to reach a compromise.
''There has been no agreement yet on the composition of the new government, and this has to happen as quickly as possible,'' he said.
He added, ''I think the patience of the Iraqi people as well as the patience of the international community is running out.''
Khalilzad also warned of the danger of civil war. ''Whatever you thought of whether the West, the coalition, should have come in here or not,'' the ambassador said, ''now not to do everything humanly possible to make this country work would have the most serious consequences for the Iraqis for sure, but also for the region and for the world."
At Friday prayers in Kufa mosque, al-Sadr blamed all the evils on the U.S. presence and demanded a timetable for withdrawal. For the first time, he suggested a phased departure, with the Americans first leaving the cities and moving to their bases. The parliament should also ban the U.S. military from using the air, he said.
