Updated

Al Qaeda (search) in Iraq released a video Sunday claiming to show the murder of an Interior Ministry official, and the debate raged about religion's place in Iraq's much-anticipated new government as lawmakers were summoned to their second-ever session.

Supporters of interim Prime Minister Ayad Allawi criticized the involvement of the religious authority in politics, while Abdel-Aziz al-Hakim, the leader of the Shiite-led United Iraqi Alliance (search), defended the role of the clergy.

"As long as we're alive and as long as Iraq and the believers are there, we will continue to work according to the directions and the advice of the religious authority," al-Hakim told the U.S.-funded Al-Hurra TV station, according to a transcript provided by his office. "The religious authority does not want to intervene in the details. It just gives direction when it thinks it will be beneficial."

Secular-minded politicians have expressed concern about the influence of religion in the National Assembly. In a letter to the United Iraqi Alliance, politicians who ran under an Allawi coalition warned against allowing religion to play a greater role in Iraq's government, saying it could "lead to instability in the relations between political forces in the Iraqi arena."

Shiite leaders have repeatedly denied they are seeking an Islamic state, saying they plan to include Kurdish and Sunni Arabs in the government.

After meeting Sunday with Shiite cleric Grand Ayatollah Ali al-Sistani in Najaf, the top U.N. envoy in Iraq, Ashraf Qazi, said al-Sistani told him he did not intend to involve himself in any political process, except for expressing his opinion in times of crises. The alliance, which won 140 of the 275 seats in the assembly, came together under al-Sistani's guidance.

Lawmakers were expected to hold their second session on Tuesday to choose a parliament speaker and two deputies, but it was unclear if they would name the country's new president, expected to be Kurdish leader Jalal Talabani.

The first session, on March 16, was to swear in the 275-member parliament. But officials have pushed back their second session amid negotiations over Cabinet posts.

In a meeting Sunday, Alliance members named former nuclear scientist Hussain al-Shahristani as their candidate to be a deputy to the parliament speaker, Alliance negotiator Ali al-Dabagh said.

On Monday, Alliance members were expected to vote on their candidate for the president's deputy position, al-Dabagh said. They will choose between SCIRI's Adel Abdul Mahdi and Ahmad Chalabi, leader of the Iraqi National Congress, he added.

They were also expected to meet with Sunni Arabs on Monday to discuss the names of Sunni (search) candidates for the parliament speaker post and that of the other president's deputy.

Al-Hakim acknowledged the lack of progress was creating frustration, saying: "We are not comfortable with this delay, and we are sorry about it."

"As long as there is a delay in forming the government, there will be a delay in providing services," he said. "But the process is not easy by nature, especially with the basis that we put: to have everyone participate and to have a national unity government."

In an interview with CNN's "Late Edition," Army Gen. John Abizaid, the commander of U.S. Central Command, said there had been progress, but that it was slow, adding: "The more uncertainty, the greater chance for escalated violence."

Violence continued Sunday, with gunmen killing a local official from the Supreme Council of the Islamic Revolution in Iraq, or SCIRI, and two of his relatives. Police discovered their bodies Sunday in an abandoned car north of Baqouba, 60 kilometers (35 miles) northeast of Baghdad. The motive for the attack was unclear. SCIRI also led by al-Hakim, is one of the main parties in the Alliance.

Militants from Abu Musab al-Zarqawi's terror network also posted a video on the Internet that showed the purported execution of a man identifying himself as Col. Ryadh Gatie Olyway.

There was no way to independently authenticate the video.

The man displayed his Interior Ministry identification card and said he was a liaison officer with the American forces. Behind the men was the black banner of Al Qaeda in Iraq.

Dressed in a brown shirt and jacket and beige pants, Olyway said he provided the U.S. military with the names "of officers of the former Iraqi army, who are Sunnis, and their addresses." At the end of the video, Olyway was blindfolded and appeared to be shot once in the head.

An Interior Ministry official, who spoke on customary condition of anonymity, said Olyway worked as a liaison officer between the interior and oil ministries and was kidnapped more than a month ago. He had not seen the video, and could not confirm whether the hostage was Olyway.

In Baghdad, bodyguards for Science and Technology Minister Rashad Mandan Omar opened fire on a crowd of protesters who had gathered in front of the ministry's offices to demand their full wages, said Hamid Balasem, an engineer at the Science and Technology Ministry.

Balasem said about 50 ministry guards were demonstrating because they said they were paid only part of their wages.

"We didn't carry any weapons or have any intention of shooting, but the minister's body guards started firing on us," said Haithem Jassim, one of three people injured in the melee.

It was unclear why the guards opened fire. No one was immediately available to comment at the ministry.

Also Sunday, insurgents hit a police patrol with a roadside bomb in the southern oil city of Basra, injuring one nearby civilian, Lt. Col. Karim Ali Al-Zaydi said. They also damaged an oil pipeline in northern Iraq, halting exports to Turkey, oil officials said. The pipeline has been targeted often in the past.

The U.S. military said an unmanned aerial vehicle crashed early Sunday near Balad, 80 kilometers (50 miles) north of Baghdad. The cause was under investigation.

A roadside bomb also exploded 40 kilometers (25 miles) north of Baghdad near a U.S. supply convoy, while a car bomb blew up near U.S. soldiers in the northern city of Mosul, witnesses said. U.S. military officials had no information on the blasts.