American flags were set on fire Friday to chants of "no, no for occupation" as followers of an anti-U.S. Shiite cleric marked the sixth anniversary of the Iraq war.
In five other Iraqi cities, supporters of cleric Muqtada al-Sadr also either marched or stood in protest after prayers to demand the release of their allies detained at Iraqi and U.S.-run prisons.
The protests came as a suicide bomber in Fallujah killed an Iraqi police officer and five other people, including civilians, in an attempted attack on the home of the local leader of Sunni security volunteers who turned against Al Qaeda.
In Baghdad, al-Sadr aide Sheik Haidar al-Jabiri urged supporters to join an April 9 march to protest the six-year anniversary of Americans taking over the city.
"Today, a remembrance of the cruel occupation of Iraq, and on April 9, there will be a chant for liberation," al-Sadr aide Sheik Haidar al-Jabiri told worshippers gathered in Baghdad's Shiite district of Sadr City for Friday sermons.
He added: "Sayed Muqtada invites you to march by the millions on April 9, the anniversary of the cruel occupation."
Baghdad fell to U.S. forces on April 9, 2003. The war began with a missile and bombing attack on south Baghdad before dawn on March 20, 2003 — March 19 in Washington.
A similar planned march last year was canceled. Al-Sadr's previous demonstrations have attracted thousands of supporters, but have not reached 1 million.
Demonstrators responded by lifting a banner reading: "To the Iraqi government, when you will be trustful and release our detainee sons?"
"No, no for occupation. Yes, yes for liberation. Yes, yes for Iraq," the demonstrators chanted.
Two American flags were set on fire.
Thousands of Sadrist followers in five other cities — Basra, Kut, Diwaniyah, Amarah and Nasiriyah — also took to the streets Friday in an apparent planned series of protests.
In Kut, up to 1,000 worshippers marched from the grand mosque in center of the city to Sadrist offices a short distance away, denouncing the U.S. occupation and calling for detainees to be released.
Outside Fallujah, an Iraqi police officer and a small groups of civilians died Friday while trying to stop a suicide bomber from reaching the home of Saadoun al-Eifan, who runs the local branch of the Sunni volunteers, the Sons of Iraq.
Police Maj. Hamed al-Jumaili said the bomber was trying to get past guards monitoring a bridge in rural Albu Eifan, where Eifan lives, about six miles south of Fallujah. He detonated his explosives belt after bring confronted by the police officer and residents, Jumaili said.
The protests and bombings came a day after a U.S. airstrike on a militant hideout north of Baghdad killed at least 11 insurgents, the U.S. said.
A search of the site by ground forces after the strike found a cache of weapons, munitions and parts to build improvised explosive devices, U.S. military spokesman Maj. Derrick Cheng said Friday.
Cheng did not immediately know Friday whether any civilians were killed or injured in the strike, or exactly when it occurred. He said the suspected insurgents were hiding near several bunkers south of Balad Ruz in Diyala province — about 45 miles northeast of Baghdad.
An Iraqi security official, speaking on condition of anonymity because he was not authorized to talk to the media, said the strike took place Thursday morning.
Meanwhile, the U.S. military announced the Thursday death of an American soldier from non-combat causes in Iraq.
A statement issued Friday did not identify the soldier, or give any details about where or how the death occurred. It said the soldier's division operates in an area south of Baghdad.
At least 4,260 American service members have died in Iraq since the war started, according to an Associated Press count.