Under pressure to take stronger action against sectarian violence, the ministry in charge of Iraq's police force will change top commanders and has already fired some 3,000 employees accused of corruption or rights abuses, a spokesman said Saturday.

The Shiite-led police force is widely accused of being infiltrated by Shiite militias blamed in slayings of Sunni Arabs, and critics say Prime Minister Nouri al-Maliki has been reluctant to move against the militias since many are linked to parties in his coalition.

Thousands have died this year in the cycle of killings between Shiites and Sunnis death squads. At least 14 other people were killed Saturday, mostly in sectarian violence around the country.

Also, the bodies of 17 Shiite construction workers were found in an orchard outside Baghdad, kidnapped and decapitated in apparent retaliation for an attack on Sunni Arabs last week.

CountryWatch: Iraq

The workers' headless bodies were found Friday outside the city of Duluiyah, 45 miles north of Baghdad, along with four other unknown victims, also beheaded.

The killings of the workers were apparently retaliation for the kidnapping on Wednesday of three Sunni Arabs in Duluiyah by a Shiite militia, police said. The three were killed and their bodies burned.

When the current government was formed in May, Interior Minister Jawad Bolani was brought to his post — in charge of police forces — in large part because he had no militia links. But his lack of militia connections has also given him less leverage to make change.

Spokesman Abdul-Karim Khalaf said the ministry intended to carry out a shake up to ensure stronger action to stop the violence.

"We are working on reshuffling the ministry's vital posts like (the leaders of the) police commandos and public order forces, as well as some undersecretaries," he told The Associated Press, without elaborating.

He said most of the 3,000 employees who had been removed since May were suspected of corruption or human rights violations, but did not specify whether they were involved in militia activities. Up to 600 of them will face prosecution, he said.

Earlier this month, an entire brigade of some 700 policemen were suspended from service and taken to barracks because of suspected militia sympathies. The commander of one of the brigade's battalions faces criminal prosecution.

The troops were suspected of allowing Shiite militias to carry out a mass kidnapping of some two dozen people from a frozen food factory in Baghdad. At least seven of those kidnap victims have since been found dead.

Still, Khalaf played down the role of the ministry's police forces in militia violence, blaming instead the Facilities Protection Service, rather than the police. The FPS, created to guard government buildings and infrastructure, has some 150,000 members but an unclear command structure.

The FPS "is part of the problem in the death squad activities. They are not working under the supervision of either the Interior of the Defense Ministry but under the ministries that use them," Khalaf said. U.S. commanders have also said FPS members may be carrying out a large portion of the killings.

Authorities are investigating the assassination on Friday of Col. Salam al-Maamouri, a commander of the elite Scorpions police battalion, which was tasked with going after both Sunni insurgents and Shiite militias.

Al-Maamouri, a Shiite, was killed along with an aide in his office in the southern city of Hillah when a bomb exploded. Initial reports said the bomb was hidden beneath his desk, though Capt. Muthana Khlaid Ali, a spokesman for the provincial police force, said Saturday it may have been set in the office window from the outside.

Al-Maamouri was believed to have received threats from Shiite militias in the area because he was taking action against them. The militias were demanding his forces stay out of areas under their control and pressing him to release jailed fighters, one aide of the colonel told The Associated Press, speaking on condition of anonymity out of fear of reprisals.

The Interior Ministry's Khalaf said the assassination appeared to have had help from "elements inside his office."

Al-Maamouri, 35, and other former army offices established the Scorpion battalion in July 2003 and later it was incorporated into the police. "He was a tough man who paid no regard to ethnic background and didn't operate along sectarian lines," said Hussein Abdul-Sada, a member of Hillah's provincial council.

In Saturday's bloodiest attack, seven people were killed in an early morning mortar attack on a small Sunni village near Baqouba, 35 miles northeast of Baghdad. Residents blamed Shiite militias.

Residents said the attack came after the Iraqi army had raided the village and another nearby. "After that, the militia attacked," a middle-aged man told AP Television News at a Baqouba hospital where he was seeking injured relatives.