The Pentagon has lost track of 190,000 AK-47 rifles and pistols given to Iraqi security forces, the Washington Post reported.
The Government Accountability Office is reportedly conducting a review after a July 31 report revealed that Iraqi insurgents may have gotten their hands on weapons and body armor intended to equip Iraqi troops. One senior Pentagon official told the Post that some of the weapons likely are being used against U.S. forces.
Meanwhile, the violence in Iraq continued unabated Monday as a homicide bomber slammed his truck into a densely populated residential area in the northern Iraqi city of Tal Afar on Monday, killing at least 28 people, police said. Most of the dead were women and children, the mayor said.
A bomber slammed his truck into a densely populated residential area in the northern Iraqi city of Tal Afar on Monday, killing at least 28 people, including 19 children, local authorities said.
The attack occurred in a crowded Shiite neighborhood of the religiously mixed city, about 250 miles northwest of Baghdad.
The powerful blast caused houses to collapse in the morning as many families were getting ready for the day, and officials said the death toll could rise.
"Rescue teams are still searching for casualties among the rubble," said Ali Abbo, the head of the human rights committee.
He said the hospital in Tal Afar had been filled to capacity, forcing the ambulances to take many victims to Dahuk, about 45 miles to the north. At least 40 others were wounded, said Brig. Gen. Rahim al-Jibouri, commander of Tal Afar police.
The attacker drove a dump truck filled with explosives and covered with a layer of gravel, Brig. Gen. Najim Abdullah said, adding that at least 19 children were among the 28 killed.
Within an hour of the attack, authorities imposed a complete curfew on the city, he said.
In Baghdad, lawmakers said that five Cabinet ministers loyal to Iraq's first post-Saddam leader will boycott government meetings, further deepening the political crisis that threatens to swamp the administration of Prime Minister Nouri al-Maliki.
The boycott of the Iraqiya List ministers loyal to former Prime Minister Ayad Allawi leaves the government, at least temporarily, with no Sunni participants. It was a deep blow to al-Maliki's attempts to reconcile the country's majority Shiites and minority Sunnis and Kurds.
Iraqiya List lawmaker Iyad Jamal-Aldin said the Allawi bloc decided to boycott because al-Maliki has failed to respond to demands for political reform issued five months ago. He said the boycott was not tied to the decision last week by the top Sunni political bloc to pull its six ministers out of the 40-member Cabinet.
The Iraqi Accordance Front left the government Aug. 1 because of al-Maliki's failure to respond to a set of demands, including the release of security detainees not charged with specific crimes, the disbanding of militias and the participation of all groups represented in the government in dealing with security issues.
The latest boycott raises to 17 the number of government ministers who have either suspended membership or quit this year.
The U.S. and Iranian ambassadors met Monday for their third round of talks in just over two months. A U.S. embassy spokesman called the talks between U.S. Ambassador Ryan Crocker and his counterpart, Hassan Kazemi Qomi, "frank and serious."
The meeting, which lasted about two hours, came after U.S., Iraqi and Iranian experts held their first talks as part of a security subcommittee, according to the U.S. Embassy.
At the subcommittee meeting, the Iranian delegation criticized what it called America's "suspicious" security approach toward Iraq and called for "a change in the broad policies and approach of the U.S.," according to the official Islamic Republic News Agency.
In other violence, a U.S. soldier was killed and two were wounded Sunday during fighting in eastern Baghdad, the military said. Eastern Baghdad is predominantly Shiite and has seen frequent attacks on U.S. forces by Shiite militia fighters.
Elsewhere, 60 bodies were found in a mainly Sunni area that had been under the control of al-Qaida in Iraq west of Baqouba, according to a Diyala provincial police official. U.S. and Iraqi forces recently have touted successes in an operation aimed at restoring control in the volatile region northeast of Baghdad.
At least 29 people were killed or found dead in other parts of Iraq, according to police who spoke on condition of anonymity because they weren't authorized to disclose the information.
Meanwhile, authorities girded for a major Shiite pilgrimage later this week in Baghdad to commemorate the 8th century death of Imam Moussa ibn Jaafar al-Kadhim, one of the 12 principal Shiite saints who is buried in a mosque in the northern neighborhood of Kazimiyah.
The procession was struck by tragedy in 2005, when thousands of pilgrims panicked by rumors of a suicide bomber broke into a stampede on a bridge, leaving some 1,000 dead. Police later said no explosives were found on the bridge and poor crowd control and the climate of fear in Iraq were largely to blame. Sunni insurgents have often targeted such gatherings to foment sectarian war.
Brig. Gen. Qassim al-Moussawi, an Iraqi military spokesman for Baghdad, said security forces would intensify checkpoints during this week's pilgrimage and marchers would be banned from carrying weapons, cell phones and even bags. It was not clear those restrictions would be enforced.
Al-Moussawi said the government was also considering a driving ban but had not made a decision.Complete coverage is available in FOXNews.com's Iraq Center.