A member of an influential Sunni clerics' group that has called for a boycott of Iraqi national elections was assassinated Monday, one day after government officials announced that the vote would be held early next year despite rising violence.

Sheik Faidh Mohamed Amin al-Faidhi, a member of the Association of Muslim Scholars (search), was shot by gunmen at his home in northern Mosul.

Elsewhere Monday, a U.S. patrol that came under attack returned fire, killing two attackers, eyewitnesses said. The incident took place in Hawija, about 150 miles north of Baghdad. The U.S. military had no immediate confirmation.

And Iraqi security forces recovered 12 bodies, including five decapitated ones, from an area south of Baghdad, police said Monday. One was identified as a member of the Iraqi National Guard. The bodies were found during a raid Sunday in Latifiyah, about 20 miles south of Baghdad, said Lt. Adnan Abdullah.

A rocket slammed into a residential district in the center of Baghdad on Monday, injuring five people including a child, witnesses said. The blast sent a giant cloud of black smoke rising over the eastern side of the Tigris River.

The military also said Monday a U.S. soldier died after he was wounded in an attack the night before in Baghdad. At least 1,222 members of the U.S. military have died since the beginning of the Iraq war in March 2003, according to a tally by The Associated Press.

On Sunday, the recently dismissed police chief of Mosul was arrested after allegations that his force allowed insurgents to take over police stations during an uprising in the northern city earlier this month, Deputy Gov. Khasro Gouran said.

Brig. Gen. Mohammed Kheiri Barhawi (search) was arrested Sunday by Kurdish militiamen in the city of Irbil, where he had fled after being fired in the wake of the uprising

Elections to Be Held Jan. 30

Iraq's first elections since the collapse of Saddam Hussein's dictatorship were scheduled for Jan. 30, and Iraqi authorities said ballots would be cast even in volatile areas — including Fallujah, Mosul and other parts of the Sunni Triangle.

The vote for the 275-member National Assembly is seen as a major step toward building democracy after years of Saddam's tyranny.

The ongoing violence, which escalated this month with the U.S.-led offensive against Fallujah, has raised fears voting will be nearly impossible in insurgency-torn regions — or that Sunni Arabs angry at the U.S.-Iraqi crackdown will reject the election.

If either takes place, officials fear the vote's legitimacy could be undermined.

U.S. forces continued to pound enemy positions in Fallujah Sunday night as Marines said they found gruesome torture houses in the terror hotbed. American commanders said U.S. and Iraqi forces had killed more than 1,000 enemy fighters during the eight-day battle there.

U.S. and Iraqi troops continued to clear the last of the resistance from Fallujah, the main rebel bastion stormed Nov. 8 in hopes of breaking the back of the insurgency before the election.

Secretary of State Colin Powell said he believed the retaking of Fallujah did "serious damage" to the insurgency.

Iraq's interim prime minister, Ayad Allawi (search), said the assault on Fallujah was necessary to ensure elections happened on time. He added that the town no longer offered a safe haven to those who wanted to stop democracy.

"We went to Fallujah and we broke their back," he told AP. "We found enough weapons there to destroy an entire country."

Allawi added that the "forces of darkness and terrorism" would also fail to benefit "from this democratic experience" and that the nation was "determined that this experiment succeeds."

Twenty nations, including Iraq's neighbors and Western and Arab countries, also gathered in the Egyptian resort of Sharm al-Sheik for a conference aimed at showing support for Iraq.

The delegates intended to call on Allawi's government to reach out to its opponents to encourage broad participation in the election. According to a draft of the conference's final statement, they were also to underline their condemnation of "terrorism" in Iraq — a boost to Allawi's and the U.S. military's crackdown on insurgents.

Meanwhile, Iraq's leading Shiite cleric condemned the U.S.-Iraqi raid on a Sunni mosque in Baghdad on Friday, an official from his office said Monday.

The official, who identified himself only as Sheik Besheer, said Grand Ayatollah Ali al-Sistani (search) condemned the raid on the Abu Hanifa mosque (search). A spokesman for al-Sistani was interviewed on Al-Manar, the television station of the Iranian-backed militant Lebanese Shiite group Hezbollah.

"The raid on Abu Hanifa mosque is unacceptable, and we denounce and condemn this action," spokesman Hamed al-Khafaf told Al-Manar. "Abu Hanifa mosque is a sacred place and a scientific university and they have to deal with it on this basis like other sacred places."

On Friday, Iraqi security forces, backed by U.S. troops, raided the mosque — one of the country's most important Sunni places of worship — killing three and wounding five others. About 40 people were detained.

The Iraqi government has warned that Islamic clerics who incite violence would be considered as "participating in terrorism." Some already have been arrested, including members of the Association of Muslim Scholars.

Farid Ayar, spokesman of the Independent Electoral Commission of Iraq, insisted that "no Iraqi province will be excluded because the law considers Iraq as one constituency, and therefore it is not legal to exclude any province."

To bolster Iraq's democracy, 19 creditor nations — including the United States, Japan, Russia and many in Europe — agreed Sunday to write off 80 percent of the $38.9 billion that Iraq owed them. Iraq owes another $80 million to other, mostly Arab countries.

'Atrocity Sites' Uncovered

In Fallujah, Marine Maj. Jim West said Sunday that U.S. troops had found nearly 20 "atrocity sites" where insurgents appear to have imprisoned, tortured and murdered hostages. West said troops found rooms containing knives and black hoods, "many of them blood-covered."

Marine Lt. Col. Daniel Wilson was quoted as saying that Fallujah terrorists had "a sick, depraved culture in the city."

West said the Marines found hostages chained to the walls and that many floors and walls were found covered in blood. Military intelligence officers also say they found a house that they believe notorious terror leader Abu Musab al-Zarqawi (search) visited.

Meanwhile, the U.S. military continued to investigate a Nov. 13 incident in which an NBC cameraman taped a Marine from the 1st Marine Division shooting a wounded insurgent lying in a Fallujah mosque. Marines could be heard yelling that the man was pretending to be dead.

The storming of Fallujah has heightened tensions throughout Sunni Arab areas, triggering clashes in Mosul, Beiji, Samarra, Ramadi and elsewhere.

In Ramadi, 70 miles west of Baghdad, insurgents ambushed an Iraqi National Guard patrol, killing eight guardsmen and injuring 18 others, police said.

The clerical leadership of the country's Shiite community, believed to comprise about 60 percent of Iraq's nearly 26 million people, has been clamoring for an election since the April 2003 collapse of the Saddam regime.

Voting is also expected to go smoothly in northern areas controlled by the Kurds, the most pro-American group, who are mostly Sunni Muslim but of Persian, not Arab, stock.

However, Sunni Arabs, estimated at about 20 percent of the population, fear domination by the Shiites, long Iraq's oppressed majority. Sunni clerics have called for a boycott of the vote because of the Fallujah attack.

During the January election, Iraqis will choose a National Assembly to draft a new constitution. If it's ratified, another election will be held in December 2005.

Voters in January also will select 18 provincial councils, and in Kurdish-ruled areas, a regional assembly.

A stable, legitimate government could enable the United States to begin reducing its 138,000-strong military presence and gradually hand over security responsibility to Iraqis.

"Having elections in Iraq are very important, and having them on time is also so important for the Iraqi people to have more security in Iraq," said Salama al-Khafaji, a Shiite member of the interim Iraqi National Council (search), a government advisory body.

Ayar, the election commission spokesman, said 122 political parties were registered for the elections. The commission has asked the United Nations to send international monitors; 35 experts already have arrived.

FOX News' David Piper and The Associated Press contributed to this report.