By Janine Zacharia and Aziz Alwan
Sunday, September 19, 2010; 3:17 PM
BAGHDAD - Six car bombs detonated across Baghdad on Sunday and a suicide bomber exploded a car in nearby Fallujah, killing a total of 37 people and wounding more than 100 in the deadliest day of violence in Iraq since the United States announced the end of combat operations three weeks ago.
The scope of Sunday's attacks -- especially a pair of simultaneous car bombings -- illustrated how uncertain the security situation remains as the United States hands over more security responsibility to its Iraqi counterparts and a political void deepens each day that Iraqi leaders fail to form a new government .
Traffic snarled in parts of Baghdad as Iraqi police tightened checkpoints after the twin car bombings struck at 10 a.m. in the Mansour and Kathumya neighborhoods, killing 29 people and wounding 111, according to Iraqi security authorities.
Witnesses said the booby-trapped vehicle in Mansour targeted a busy market area near an office of the Asiacell phone company and a popular restaurant. Ten people died.
The car bomb in Kathumya, which killed 19, detonated near an office of Iraq's National Security Ministry.
"It was a big explosion, and dust and smoke filled my house,'' Abu Shahad, who lives about 200 yards from the blast site told the Associated Press. "I went out and saw a big black cloud hanging over the area where the bomb exploded, and I rushed there because I have relatives living there." He said his cousin and her child were killed and another cousin was wounded.
A third bomb planted on a bus killed the driver and his son.
A prominent Iraqi tribal leader, Salih Ali Hamdan, was killed when his car exploded.
Bombs that detonated in the parked vehicle of a senior Iraqi intelligence official and in a garage did not cause fatalities.
In Fallujah, a former stronghold of a Sunni Muslim insurgency 40 miles west of Baghdad, four civilians and one Iraqi soldier were killed when a suicide car bomber, targeting an Iraqi army patrol, was stopped near a bakery. A similar attack occurred in the same spot three weeks ago.
Also Sunday, three rockets were fired at the U.S. Embassy, Iraqi security authorities and American witnesses said. A fourth rocket landed in the Baghdad neighborhood of Jadriya. There were no casualties from either rocket attack.
Special correspondents Aziz Alwan and Jinan Hussein in Baghdad contributed to this report.