The bodies of 18 men, bound, blindfolded and strangled, were found Wednesday in a Sunni Arab district of Baghdad, while gunmen in police commando uniforms seized some 50 employees from a private security firm in the capital. Iraq's Shiite vice president, meanwhile, signed a presidential decree calling Parliament into session, breaking a major logjam that had delayed the creation of a unity government.

The 18 bodies discovered by U.S. troops in western Baghdad late on Tuesday had all been garroted and had their hands bound with plastic ties, police and hospital officials said. The victims, a mixture of middle-aged and young men in civilian clothes, carried no identifying papers, police said.

A policeman at the Yarmuk hospital morgue pointed to their clothing and long hair as an indication some may have been religious extremists linked to Al-Qaeda. Reuters reporters who saw the bodies said many appeared to be Iraqis.

Police sources said only one had so far been identified by a relative. He was a guard at an oil refinery in southern Baghdad.

The policeman at the hospital said many of the bloodied bodies appeared to have been beaten while some had small burn marks, suggesting they were tortured before being killed.

Senior officials, aware of the potential for sectarian anger if it becomes clear all are either Sunnis or Shiites, made no formal comment on the religious identities of the dead.

Iraqi police said the bodies were dumped near the Amriyya district, a stronghold of insurgent groups.

Less than 24 hours after the discovery of the bodies, men in police uniform stormed the Al-Rawafed security firm headquarters in the east of the capital and made off with all the employees at gunpoint, said Interior Ministry Major Falah al-Mohammadawi. The victims did not resist because they assumed their abductors were police special forces working for the Interior Ministry, Mohammadawi said.

Interior Ministry Undersecretary Major General Ahmad al-Khefaji denied any involvement by his department, saying: "It is a terrorist act."

But two other officials, speaking on condition of anonymity, said the private guards had been arrested by genuine police commandos. One senior official in the Interior Ministry said police raided the company after a complaint from a corporate client dissatisfied with the firm's security services.

Iraq's Shiite interior minister, accused by Sunnis of condoning death squads, escaped an apparent murder attempt Wednesday when a roadside bomb blasted his convoy. Minister Bayan Jabr, however, was not in his car.

In other violence on Wednesday, at least 11 Iraqis were killed and scores of others wounded in a series of rebel attacks.

The violence has complicated faltering efforts to form a government of national unity three months after elections.

But Vice President Adel Abdel-Mehdi's signature on an executive order opened the way for the much-delayed first session of the Parliament.

"I expect the first session to be held Sunday or by the end of next week at the latest," said Nadim al-Jabiri, head of one of seven Shiite parties that make up the United Iraqi Alliance, the largest bloc in Parliament.

He added negotiations were still under way on a specific date.

Iraq's politicians are locked in a dispute over whether outgoing Premier Ibrahim al-Jaafari should head a new coalition government.

Iraqi leaders are due to meet President Jalal Talabani Thursday to decide on a way forward.

The first session had been delayed by weeks of intense political infighting and reached an impasse after Abdel-Mehdi refused to sign Talabani's decree Monday.

A key Shiite political figure, speaking anonymously, said Abdel-Mehdi had acquiesced after American Ambassador Zalmay Khalilzad sought the intervention of powerful Shiite leader Abdel-Aziz al-Hakim in breaking the stalemate in talks Tuesday.

Abdel-Mehdi heads the Shiite parliamentary bloc loyal to Hakim, who leads the Supreme Council for the Islamic Revolution in Iraq.

Jabiri, however, said the decision to sign was taken on advice from Iraq's Federal Court, which said Parliament could be convened through an alternative process if Abdel-Mehdi continued to hold out.

In other developments, the U.S. military announced the release of 122 male detainees after a joint U.S.-Iraqi board reviewed their cases.

Giovanni Di Stefano, a lawyer representing former Saddam Hussein government officials, said those released included two of the 50 previously "most wanted" in Iraq.

Former Deputy Premier Abdel-Tawab Mullh Huwaysh was 10 of hearts in the "deck of cards" of most wanted Iraqis issued by U.S. forces, while former ruling Baath Party regional commander Saad Abdel-Majid al-Faisal was three of clubs.