BAGHDAD, Iraq - Violence killed at least 29 people Sunday, including three U.S. soldiers, and mortar fire rumbled through the heart of Baghdad despite stringent security measures to counter sectarian violence.
A ban on driving in Baghdad and its suburbs helped prevent major attacks during daylight Sunday, but after nightfall, explosions thundered through the city as mortar shells slammed into a Shiite quarter in southwestern Baghdad, killing 16 people and wounding 53, police said.
Mortar fire also hit a Shiite area on the capital's east side, killing three people and injuring six, police reported.
Nevertheless, officials announced they would let vehicles back on the streets at 6 a.m. Monday.
The vehicle ban, which followed a citywide curfew that kept everyone inside for two days, was part of emergency measures imposed after Wednesday's bombing of a Shiite shrine. The attack triggered a wave of reprisal attacks on Sunni mosques and clerics, pushing Iraq to the brink of civil war.
With the relaxation of emergency measures, officials said that Monday would present a major test of whether the worst of the crisis had passed. As dawn approached, the roar of U.S. jet aircraft could be heard patrolling the skies over this tense city.
Although mosque attacks have declined sharply, sectarian violence went unabated Sunday.
A bomb exploded at a Shiite mosque in the southern city of Basra, injuring at least two people, police said.
More than 60 Shiite families fled their homes in predominantly Sunni areas west and north of Baghdad after receiving threats, said Shiite legislator Jalaladin al-Saghir and Iraqi army Brig. Gen. Jalil Khallaf.
North of the capital, gunmen stepped from a car and fired on teenagers playing soccer in a Shiite-Sunni mixed neighborhood of Baqouba, killing two of the youths and wounding five, police said.
In other violence, two U.S. soldiers died when their vehicle was struck by a roadside bomb in western Baghdad, the U.S. military said. A third soldier was killed by small-arms fire in central Baghdad late Sunday, the military said.
Their deaths brought to at least 2,290 the number of members of the U.S. military who have died since the beginning of the Iraq war in March 2003, according to an Associated Press count. The figure includes seven military civilians.
The sectarian crisis threatened U.S. plans for a government drawing in the country's major ethnic and religious parties, considered essential to win the trust of the disaffected Sunni Arab minority that forms the backbone of the insurgency.
With a broad-based government in place, the Bush administration hopes to begin withdrawing some of its 138,000 soldiers this year.
A former British ambassador to Iraq predicted Sunday that increasing sectarian bloodshed would require the U.S.-led foreign military coalition to stay for some time to help keep peace among rival ethnic and religious groups.
"One could almost call it a low-level civil war already," Sir Jeremy Greenstock, who was Britain's envoy in Baghdad until 2004, told British television channel ITV1.
During a meeting at Prime Minister Ibrahim al-Jaafari's residence, representatives of the main political parties agreed late Saturday to renew efforts to form an inclusive government.
But Sunni politician Nasir al-Ani said Sunday that his side was looking for some tangible steps before ending its boycott of government talks.
Sunni and Shiite religious leaders have also called for unity and an end to attacks on each other's mosques.
Radical Shiite cleric Moqtada al-Sadr, whose own militia was blamed for many of the attacks on Sunnis, repeated the appeal Sunday when he addressed followers in the southern Shiite stronghold of Basra upon his return from neighboring Iran.
He accused Americans and their coalition partners of stirring up sectarian unrest and demanded their withdrawal.
Meanwhile, Iraqi police said they had found no trace of abducted American journalist Jill Carroll as the deadline set by her kidnappers for killing her passed at midnight Sunday with no word on her fate.
The freelance journalist, who was doing work for the Christian Science Monitor, was abducted Jan. 7 in Baghdad. She was last seen on a videotape broadcast Feb. 10 by a Kuwaiti television station, which said the kidnappers threatened to kill her unless the United States met unspecified demands by Sunday.
An Interior Ministry official said Sunday that authorities had stepped up their search for the 28-year-old woman but made no progress.
Also Sunday, the Arabic-language Al-Jazeera satellite channel broadcast a tape it received from the family of Canadian hostage James Loney appealing for his release and that of three colleagues from the Christian Peacemaker Teams abducted with him in Baghdad on Nov. 26.