An arrest warrant was issued against Iraq's Sunni culture minister, and police raided his home on Tuesday after he was accused of ordering a 2005 assassination attempt against a secular Sunni politician that killed his two sons, officials said.

The main Sunni political bloc immediately demanded the decision be reversed.

Culture Minister Asad Kamal al-Hashimi, who was not home during the raid, was identified by two suspected militants as the mastermind of a Feb. 8, 2005, ambush against then-parliamentary candidate Mithal al-Alusi, according to Ali al-Dabbagh, a government spokesman. Al-Alusi escaped unharmed but two of his sons were killed.

"The two who planned and carried out the killings of Mithal al-Alusi's two sons confessed that they took orders from him," al-Dabbagh said. He added that al-Hashimi was a mosque imam at the time.

Al-Dabbagh said the arrest warrant was issued for the killings of al-Alusi's sons, not the failed attempt against the politician. He also said al-Hashimi's status as a Cabinet minister provides no immunity.

Al-Hashimi was the first full Cabinet minister to face arrest, although Iraqi authorities have arrested other senior officials, including the deputy health minister who was linked to Shiite militiamen loyal to radical cleric Muqtada al-Sadr.

Prime Minister Nouri al-Maliki, a Shiite, has promised not to let political or sectarian considerations stop him from cracking down on violence, but the warrant against a prominent Sunni politician could set back efforts to bring the disaffected minority into the political process.

Al-Hashimi's party, the hardline Congress of the People of Iraq, condemned the arrest warrant and warned the Shiite-dominated government to avoid "playing with fire by continuing the policy of fabricating lies to exclude Sunni politicians and officials from the Iraqi arena."

Al-Hashimi said he was being targeted unfairly and accused the government of trying to sideline the leadership of the biggest Sunni parliamentary bloc, the Accordance Front, which comprises his party, as well as the moderate Iraqi Islamic Party and the National Dialogue Council.

"When they want to get rid of anybody, the easiest way for them to do that is to charge him with terrorist activities," he said in an interview with the pan-Arab satellite channel Al-Jazeera.

"They have ready-made charges and they use them against us so that they can chase us out of the country," he added.

Muhanad al-Essawi, an Accordance Front spokesman, said U.S. and Iraqi forces raided al-Hashimi's house and detained several guards. The U.S. military denied involvement in the raid.

"Iraqi authorities have issued an arrest warrant against al-Hashimi over fabricated terrorism charges," al-Essawi said.

The bloc later issued a statement denouncing the raid and the arrest warrant, saying it was based on information from detainees who had been tortured; the statement said al-Maliki had promised that al-Hashimi would not be arrested.

"The prime minister promised to stop all the procedures against the culture minister because it is not legal and the minister has immunity, but what happened was to the contrary," the statement said, adding another appeal was issued on Tuesday.

The statement said al-Maliki had ordered the guards released and the proceeding against the culture minister halted: "We are fed up and there is no room for patience and we wish that this mistake would be fixed and not repeated."

A government official, speaking on condition of anonymity because he was not authorized to disclose the information, said the arrest warrant was a judicial matter and denied that al-Maliki had given guarantees that al-Hashimi would not be arrested.

Al-Alusi was a leading figure in the secular Iraqi National Congress Party of former Pentagon favorite and secular Shiite Ahmad Chalabi, but he was expelled from the party after visiting Israel. He was elected to parliament as the head of his own group, the Iraqi Democratic National Party, which holds one seat.

Sectarian violence persisted in Iraq. Hamid Abdul Farhan al-Shujairi, a Sunni sheik, was killed in the mainly Sunni neighborhood of Sadiyah, a policeman said, speaking on condition of anonymity because of security concerns.

Another member of the same tribe, Akram al-Shujairi, said the sheik had attended a conference several weeks ago on supporting the government and fighting al-Qaida.

The attack came a day after a suicide bomber slipped into the busy Mansour Hotel in Baghdad and blew himself up in the midst of a gathering of U.S.-allied tribal sheiks, killing 13 people and undermining efforts to forge a front against the extremists of al-Qaida in Iraq. As many as six of the tribal chiefs were among the 13 victims, police said.

U.S. Marine Maj. Jeff Pool, a military spokesman in western Iraq, said the Anbar sheiks were meeting with Shiite sheiks to talk about reconciliation.

The U.S. command here has pointed repeatedly to the Anbar group and its opposition to al-Qaida as an example for other tribes to follow elsewhere in Iraq. But the Salvation Council reportedly has been riven by disagreements -- over how closely to work with the U.S. occupation force, for example.

Iraq's academic world also suffered more violence on Tuesday.

A top Baghdad University official was shot to death in a predominantly Sunni neighborhood in the capital. Nihad Mohammed al-Rawi was the deputy in charge of administrative affairs and head of the chemical engineering department at Iraq's main university.

In the northern city of Mosul, gunmen killed a Sunni Arab student returning home from college after final exams.

Scores of academics and students have been killed by both sides of the sectarian divided as extremists see universities as bastions of Western, non-Islamic thought.