BAGHDAD, 7 August 2007 — The United States and Iran held a “frank and serious” first meeting yesterday of a new committee set up by the archfoes to seek an end Iraq’s sectarian violence. Hours before the diplomats met, a truck bomber in a crowded residential area killed at least 33 people in their homes.

Establishing the security subcommittee has been the main achievement so far of new face-to-face contacts between Washington and Tehran — enemies that have had no diplomatic ties for almost 30 years but were driven to the negotiating table by the threat of all-out civil war in Iraq. The United States accuses Iran of fomenting unrest in Iraq by supporting Shiite militias and supplying weapons such as armor-piercing bombs used to kill US troops.

Iran denies it is responsible for violence and blames the United States for unleashing sectarian strife after its 2003 invasion. Neither country has said precisely what it hopes to achieve at the talks, which were hosted by Iraqi officials in Baghdad and led by Marcie Ries, a senior diplomat at the US Embassy, and Amir Abdollahian, the deputy head of Iran’s mission.

After the talks, which lasted several hours, a US Embassy official said they were “frank and serious, and focused as agreed on security problems in Iraq.” They would continue at a date to be agreed later. The two countries also have long-running feuds over other issues such as Iran’s nuclear program, but officials say they have not been raised in the Iraq talks.

A suicide bomber sped into a Shiite village in northern Iraq yesterday and blew up a truck packed with explosives, unleashing a massive blast that killed 33 people and pulverized homes. The bomber detonated his deadly charge after driving across farmland to Al-Quba, killing 30 people, including 12 children, and flattening mud-brick houses, the mayor of nearby Tal Afar, Maj. Gen. Najim Abdallah, told AFP.

“It was filled with a huge amount of explosives. Twenty houses were destroyed, 10 of them entirely wiped out,” said Abdallah. He said five women were among the dead and 14 people were in a critical condition in hospitals after the attack.

Bodies were pulled from the rubble of flattened homes in the village whose nearly 200 houses are built mostly from mud, and the victims were ferried to hospitals as far away as the neighboring Kurdish province of Dohuk, he said.

Bombings are increasingly common in villages, as militants flee to rural backwaters away from thousands of US and Iraqi security forces cracking down on Baghdad and other flashpoint cities under a five-month-old security plan.

Violence further south killed another 18 people, including nine wiped out when a roadside bomb ripped through an unofficial stop for one of the battered minibuses used by thousands of people in Baghdad. The device, hidden by the side of the road, blew up after a minibus stopped to collect waiting passengers in the Diyala Bridge neighborhood in the southern suburbs, security officials said.

Shrapnel sprayed the area as Iraqis got on and off the minibus shortly before the main rush hour, and as others stood waiting for a different line.