Hundreds of Shiite and Sunni Muslims prayed together Friday, then staged a joint demonstration in central Baghdad to denounce military and police raids and widespread arrests of suspected insurgents. The show of unity comes ahead of potentially divisive parliamentary elections.

Men waved Iraqi flags and women dressed in black robes carried posters of their missing sons. Some protesters held up portraits of Sunni clerics who have been killed since the U.S. invasion in 2003.

Shiites make up the majority in Iraq, but were oppressed by former ruler Saddam Hussein, who is a Sunni. Since Saddam's overthrow, Shiites have controlled most of the political power in Iraq, while the anti-U.S. insurgency has been dominated by Sunnis.

Sunni suicide bombers have targeted Shiite mosques and gatherings.

And Sunni leaders have complained of attacks by Shiite death squads tied to the government. Last month, U.S. troops discovered an interior ministry jail with 173 detainees, some showing signs of torture.

The ministry is "killing our sons at the orders of the [Iranians]," one poster read, referring to alleged ties between Interior Minister Bayn Jabr and Iran. Another poster referred to Jabr as an American agent.

In Ramadi, 70 miles west of Baghdad, the U.S. military played down reports by residents and police of widespread attacks Thursday against American and Iraqi targets in the city. The military said only one rocket-propelled grenade was fired at an observation post, causing no casualties. Insurgents left behind posters and graffiti saying they were members of Al Qaeda in Iraq.

Also Thursday, the U.S. command in Iraq said there were 23 suicide bombings in November, the lowest number in seven months. They attributed the drop to the success of U.S.-Iraqi military operations against insurgent and foreign fighter sanctuaries near the Syrian border.

But still, 85 U.S. troops died during the month, one of the highest tolls since the invasion.

Maj. Gen. Rick Lynch, a coalition operations officer, warned that Al Qaeda in Iraq, led by Jordanian terror mastermind Abu Musab al-Zarqawi, would probably step up attacks in the next two weeks to try to disrupt parliamentary elections Dec. 15.

Lynch said car bombings detonated remotely declined to 68 in November from 130 in February. However, suicide attacks have not consistently decreased over the past year. After more than 70 such attacks in May, the number fell in August by nearly half and then climbed to over 50 two months later.

And despite the decline over the past month, there has been no letup in the relentless toll of American deaths at a time of growing discontent in the United States over the Iraq war.

The U.S. command said Thursday that four American service members were killed the day before, three of them from hostile action and the fourth in a traffic accident. The deaths raised the American fatality toll for November to at least 85.

That was down from the 96 American deaths suffered in October — the fourth deadliest month since the war began in March 2003. But it was well above the 49 deaths in September. U.S. monthly death tolls have hit 80 or above during 10 of the 33 months of the war.