Dozens of militants stormed a Shiite village north of Baghdad on Saturday, killing at least 13 people and torching homes, police said. Elsewhere the same region, Iraqi and American troops freed four villages from al-Qaida control, Iraqi officials said. The militant attack on Dwelah, about 75 kilometers north of Baghdad in Diyala province, began about 6:30 a.m. with a bombardment of mortar rounds, then 50 to 60 suspected al-Qaida fighters streamed in and opened fire, forcing families to flee, a police officer said. The militants burned homes and killed at least 13 villagers, including three children and two women, the officer said, speaking on condition of anonymity because he was not authorized to release information about the raid. But the villagers fought back, police said, killing three gunmen. Elsewhere in Diyala, US and Iraqi troops, police and members of a local tribe freed four villages from al-Qaida control, killing 10 militants and arresting 15 in a two-day operation that ended Saturday, according the provincial army and police headquarters. Among the weapons and ammunition seized were 100 barrels of TNT. The American military has courted both Sunni and Shiite tribal leaders in Diyala and elsewhere, hoping they will help lead local drives against al-Qaida. A similar effort saw some success in Iraq's westernmost province, Anbar, where Sunni tribes rose up against the organization's brutal tactics and austere version of Sunni Islam. The groups now include some 60,000 Iraqis nationwide, most of them Sunni Arabs, according to senior US officers, and members have come increasing attack from al-Qaida, which is trying to offset recent security gains. At least six members of the local groups were killed on Friday and Saturday outside Baghdad and five abducted, police and group members said. US commanders have welcomed the relative lull in violence, but warn that Sunni and Shiite extremists still pose a serious threat. The US administration has pushed the Shiite-led government to capitalize on the security gains and make tangible progress toward national reconciliation. That effort has foundered, and on Saturday lawmakers from parliament's largest Sunni Arab bloc walked out of a session to protest what they called the house arrest of their leader, Adnan al-Dulaimi, following the discovery of a car bomb near his compound. US and Iraqi officials said the keys to the explosives-laden vehicle were found on one of his bodyguards. Al-Dulaimi's son and about 30 other people also were arrested Friday. Lawmakers said al-Dulaimi, a harsh critic of Shiite Prime Minister Nouri al-Maliki, told them Saturday that security forces prevented him from leaving his Baghdad home to come to parliament, which is located in the US-protected Green Zone. Also stopped from leaving was his daughter, legislator Asmaa al-Dulaimi. Chief government spokesman Ali al-Dabbagh denied in an interview with state television Saturday that al-Dulaimi was under house arrest, but added that any proceedings against him would be carried out under the law. "Everyone is subject to the law whether he is a lawmaker or not and the government is adamant to be objective and neutral in dealing with this issue," he said. Speaker Mahmoud al-Mashhadani, himself a member of al-Dulaimi's Iraqi Accordance Front, said al-Maliki told him al-Dulaimi was being held at his home for his own safety, since members of his personal security detail have been detained. However, al-Mashhadani also said a local Iraqi army commander reported there was an official arrest order for al-Dulaimi. "It's a dangerous precedent if a field commander places a lawmaker under house arrest without notifying the prime minister." Separately in southern Iraq, police captured a suspect believed responsible for supplying and coordinating roadside bomb attacks against American and Iraqi troops, the US military said Saturday. The American statement said the suspect, detained Friday in Nasiriyah, about 320 kilometers (200 miles) southeast of Baghdad, had traveled repeatedly to Iran and was found with Iranian weapons and munitions, including three new Iranian-made rockets and boosters, a launcher and AK-47 assault rifles and ammunition. Also in Iraq's south, gunmen abducted the dean of a technical institute in Amarah, a Shiite militia stronghold about 320 kilometers southeast of Baghdad, leaving behind his car and driver, according to an aide. Raid al-Saaiy was taken away by gunmen in a pickup truck, said the aide, Ahmed Ajeel. Although it was not immediately clear why al-Saaiy was targeted, Iraqi academics have fallen victim to Iraq's religious extremists and other violent groups. As of Nov. 1, 336 Iraqi academics were assassinated, according to an Associated Press count, and thousands had fled. Associates said al-Saaiy previously worked with British forces for more than a year on reconstruction and was not affiliated with either militias or politics.