Militants struck across the Iraqi capital Wednesday, killing more than 50 people, including 32 in a suicide bombing that targeted pilgrims commemorating a revered Shiite saint, Iraqi police said.
The attacks -- the deadliest of which occurred in northern Baghdad's predominantly Sunni neighborhood of Azamiyah -- offered a clear indication of the push by insurgents to exploit Iraq's political vacuum and destabilize the country as U.S. troops head home.
Police said the bloody suicide bombing that killed 32 and wounded more than 90 people, split the hot Wednesday evening air as Shiite pilgrims were about to cross a bridge leading to the a shrine in the Shiite Kazimiyah neighborhood where a revered imam is buried.
A 30-year-old Sunni resident of Azamiyah said he was drinking tea and watching pilgrims walk by when he and his friends heard the blast.
"We heard a big explosion and everybody rushed to the site to see bodies and hear wounded people, screaming for help," Saif al-Azami told The Associated Press.
"We helped carry the wounded to the hospital before the ambulances arrived," he said, adding that some of his Sunni friends who were serving food and water to the Shiite pilgrims were killed and wounded in the attacks.
Militants were able to strike even as security forces were on high alert in the capital, where Shiite pilgrims from all over Iraq converged on a mosque in the northern Baghdad neighborhood to mark the anniversary of the death of Moussa al-Kadhim, the seventh imam.
A vehicle ban was in place across Kazimiyah, and 200,000 members of security forces were deployed along the way to the shrine, searching pilgrims for weapons at various checkpoints.
Though violence has dropped across Iraq, religious processions, holy sites and security forces are still regularly targeted by insurgents trying to re-ignite sectarian bloodshed that had the nation teetering on the brink of civil war from 2005 to 2007.
Wednesday's attack took place near the bridge where 900 people died in 2005 in a stampede sparked by a rumor that a suicide bomber was among the more than 1 million people who had gathered at the Kazimiyah shrine to mark the date of the imam's death.
Iraq has been without a new government since the March 7 election, which produced no clear winner. The bickering between opposing political blocs vying to lead the country has raised fears that insurgents are exploit the uncertainty to re-ignite sectarian bloodshed.
Earlier this week U.S. vice president Joe Biden met with senior Iraqi officials in Baghdad to urge them to select new leaders for Iraq wobbly democracy without further delays. Biden met with two main contestants for the prime minister post, Nouri al-Maliki, a Shiite who currently heads the government, and his Sunni-backed rival Ayad Allawi, who narrowly won the March vote. Biden ask the two men to compromise.
Also on Wednesday, at least seven Shiite pilgrims were killed in two separate attacks in Harthiya neighborhood in western Baghdad. Twenty-nine people were wounded in the two attacks, police and hospital officials said.
In northern Baghdad, a roadside bomb targeting the devout Shiites detonated, killing two civilians and two policemen on patrol near by, police officials said.
Earlier Wednesday, police and hospital officials said two pilgrims died and seven were wounded in eastern Baghdad when a mortar shell hit their procession.
In western Baghdad, militants blew up the homes of Iraqi security officers, killing three family members.
Police officials said militants blew up the homes of two police officers, two members of an anti-al-Qaida Awakening Council and that of an ambulance driver in Wednesday's dawn attacks in Baghdad's western suburb of Abu Ghraib.
None of the targeted men were at home at the time of the attacks, but three of the men's relatives were killed, police and hospital officials in Abu Ghraib said.
Also in Abu Ghraib, an Iraqi soldier was killed and six were wounded when a suicide bomber drove an explosives-laden car into an army checkpoint. A bomb attached to a car of a police officer exploded in the same western Baghdad suburb, killing his mother and wounding his wife, police officials said.
In the predominantly Sunni neighborhood of Dora in southern Baghdad, a police major was killed when a bomb attached to his car detonated as he drove to work on Wednesday morning, police said.
All officials spoke on condition of anonymity because they were not authorized to talk to the media.
Associated Press writers Sameer N. Yacoub and Saad Abdul-Kadir contributed to this report.