Truck Bombs Kill 175 in Iraq's North

Two weeks later, 23 Yazidi factory workers were dragged off a bus and executed in Mosul in apparent retaliation for the teenager's death. Police attributed the attack to the Sunni insurgent group al-Qaeda in Iraq.

No one asserted responsibility for Tuesday's bombings. Khairi Bozani, a Yazidi who lives in Sinjar, called them the most recent step in a campaign by other Iraqi groups to drive Yazidis out of the country. "They are trying to finish the Yazidis," Bozani said. "If the girl hadn't been killed, they would have found another excuse to attack us."

In Anbar province Tuesday, five Americans died when the Chinook helicopter went down during a training flight, the military said. The cause of the crash is under investigation.

Three other U.S. soldiers were killed Monday by a roadside bomb in the province of Nineveh, in northwestern Iraq, officials said, while one was killed in combat in western Baghdad.

The bridge that was hit by a truck bomb was located in Taji, north of Baghdad.

The vehicle, a fuel tanker, had just passed through an Iraqi army checkpoint about 8:30 a.m. when it detonated on the bridge. The blast killed 10 people and sent three cars plunging into a canal that joins the Tigris River, authorities said. It also destroyed the northern section of the bridge.

The bridge had been operating with only one lane since a bombing in May. It is part of an important artery between Baghdad and Mosul, the biggest city in the north.

In recent months, suicide bombers have repeatedly attacked key bridges around the capital in an attempt to disrupt road traffic and isolate the city. In April, a truck bomb destroyed a large portion of the historic Sarafiya bridge over the Tigris River; on Sunday, a replacement floating span was officially opened.

Also Tuesday, a deputy oil minister was kidnapped by armed men at his home in the Oil Ministry compound in eastern Baghdad, according to ministry spokesman Assem Jihad. Abdel Jabar al-Wagaa, the senior assistant to Oil Minister Hussein al-Shahristani, was seized along with several other ministry staff members, Jihad said.

The abduction was carried out by gunmen wearing Iraqi security force uniforms who entered the compound late Tuesday afternoon in more than a dozen official vehicles, according to the spokesman.

On May 29, five Britons were kidnapped from the nearby Finance Ministry. No group has asserted responsibility for either incident, and the victims have not been located.

Meanwhile, the U.S. military announced that it has begun a major new offensive involving 16,000 U.S. and Iraqi soldiers in Diyala province, northeast of Baghdad. Operation Lightning Hammer is targeting fighters of al-Qaeda in Iraq in the areas surrounding Baqubah, the capital of Diyala.

The number of bombings in Baqubah and Baghdad has declined significantly since 30,000 additional U.S. troops arrived in Iraq this year. But large-scale attacks in smaller towns and rural areas have led some observers to conclude that insurgent groups have merely relocated.

In an interview last week, Brig. Gen. John M. "Mick" Bednarek, who has led the military operation in Baqubah, said that the city has been largely stabilized and that many of the 10,000 troops there would be used to expand the U.S. presence elsewhere in Diyala.

Talks among Iraq's top political leaders continued Tuesday at a summit that Prime Minister Nouri al-Maliki has said he hopes can repair his fractured government.

Maliki did not speak publicly after Tuesday's meetings, but other leaders said the discussions are to continue Wednesday.

Brwari reported from Mosul. Special correspondents Naseer Nouri and Dalya Hassan in Baghdad contributed to this report.