BAGHDAD -- Suicide bombers stalked through the leading Shi'ite Muslim mosque in Baghdad yesterday, setting off explosions that killed up to 79 worshipers and wounded more than 160 in the deadliest attack in Iraq this year.
Three blasts ripped through hundreds of faithful at the Baratha mosque, a religious center affiliated with the biggest Shi'ite religious party in Iraq's governing coalition. Some of the dead were killed as they streamed out after prayers and others as they surged back inside for cover, witnesses and police said.
In an intensifying 1 1/2-month-old campaign of violence targeting Shi'ite shrines, yesterday's attack was the second in as many days at a mosque associated with one of Iraq's Shi'ite religious parties, which rule Iraq through the loyalty of the Shi'ite majority and of the parties' armed militias.
On Thursday, a car bombing near the Imam Ali mosque in the southern city of Najaf killed at least 13 people.
The Feb. 22 bombing of a Shi'ite shrine in the largely Sunni Arab city of Samarra, north of Baghdad, has touched off Iraq's worst sectarian violence since US forces invaded three years ago. More than 1,000 people have died and tens of thousands have been driven from their homes in violence following the bombing of the Golden Mosque.
One of the bombers in yesterday's attack was dressed in the all-covering black cloak worn by Shi'ite women, hiding strapped-on bombs. Police were uncertain whether the attacker was a woman or a man wearing a woman's robe to conceal explosives.
''The ground was all flesh and blood," said Abbas Talib, 53, a gas station attendant who rushed into the Baratha mosque after the blasts and helped carry out the dead.
''Many people died inside," said Talib, who said he carried out 12 bleeding persons without pausing to see if they were dead or alive. ''Many died."
Baghdad had been on high alert amid rumors that car bombers were roaming the streets yesterday looking for targets.
At the Baratha mosque, which is associated with the Supreme Council for Islamic Revolution in Iraq, security is routinely rigid, with worshipers body-searched as they enter. But the bombers apparently slipped in as worshipers left the mosque after prayers.
The first explosion tore through worshipers at the main exit, witnesses said. Survivors rushed back inside the mosque, where a second bomb went off three minutes later. Ten seconds after that, a third bomb exploded.
Outside, survivors clambered up the fence around the mosque and leapt over, fearing more bombs. Wounded people ran through the streets, looking for a place to hide.
''Don't gather in one spot! Don't gather in one spot!" police loudspeakers warned.
Within minutes, the sealed-off streets around the shrine resembled a battlefield. Iraqi security forces broke through security cordons to carry off the wounded. As always after bombings in Iraq, bursts of automatic-weapon fire by adrenaline-charged security forces kept survivors huddling in fear long after the blasts.
Colonel Sami Jabara, a Baghdad police spokesman, said 68 people were killed. News agencies put the toll at 79, with 160 wounded.
Immediately after the blasts, police and officials from the Shi'ite movement led by cleric and militia leader Moqtada al-Sadr said two Baghdad mosques linked to al-Sadr also had been hit, with many dead. But health workers at Baghdad's main hospitals said they treated no casualties from the areas of those two mosques, and residents said they had heard no explosions.
Immediately after the Golden Mosque bombing in Samarra, Shi'ite militia fighters poured out of Sadr City, a stronghold of Sadr support in Baghdad, and al-Sadr's armed men were blamed for a wave of retaliatory attacks.
US Ambassador Zalmay Khalilzad said: ''I urge all Iraqis to exercise restraint in the wake of this tragedy, to come together to fight terror, to continue to resist the provocation to sectarian violence, and to pursue justice within the framework of Iraq's laws and constitution."
Ridah Jawad Taqi, a spokesman for the Supreme Council, repeated the Shi'ites' long-held assertion that attacks such as yesterday's were calculated provocations by those ''wishing to ignite a sectarian conflict."
Shortly before the attack, a ranking Supreme Council leader suggested the crisis had reached such a point that it was time to turn to Shi'ite religious leaders for political guidance. Shi'ites must ask Grand Ayatollah Ali Sistani, Iraq's most influential religious figure, ''to solve this crisis," Sader al-Deen al-Qubbanchi said in his sermon at a mosque in Najaf.
Efforts to form a government have been stalled for months over the reappointment of Prime Minister Ibrahim al-Jaafari, supported only by his own Dawa party and by Sadr's organization.
Yesterday, Dawa suggested for the first time that Jaafari might withdraw his candidacy, but only if another member of the party were appointed prime minister instead, an official close to the talks said. Other Shi'ite parties were said to be considering the idea.
Secretary of State Condoleezza Rice and British Foreign Secretary Jack Straw flew to Baghdad last weekend to urge the Iraqis to speed up government talks, in a move widely seen as an effort to pressure out Jaafari.
Several Iraqi figures complained yesterday that the US and British intervention had backfired, prompting Jaafari's supporters to dig in their heels against what many Iraqis considered foreign interference.
''The visit by Rice and Straw has complicated things in Iraq," Kurdish politician Mahmoud Othman said. ''The visit had a negative impact on this issue because al-Jaafari supporters are now saying that the Americans are interfering in a purely Iraqi issue."
Material from the Associated Press was included in this report.