Story Highlights• Two people wounded in Sadr City as U.S. copters hover over funerals.
• Some Sunnis burned to death as Shiites torch mosques in apparent revenge
• Shiite bloc warns of walkout if Iraq prime minister meets President Bush
• More than 200 killed Thursday in Sadr City in coordinated attacks on Shiites
Adjust font size:
BAGHDAD, Iraq (CNN) -- Enraged Shiites burned people to death, torched mosques and denounced Sunni leaders and the United States a day after a bloody assault on Sadr City, the Iraq capital's Shiite bastion.
That coordinated strike, which killed more than 200 and wounded more 250 Thursday, is considered the worst of the Iraq war, and Sunni militants are widely assumed to have carried it out.
Witnesses said Shiite gunmen on Friday attacked two mosques with rocket-propelled grenades and burned two other Sunni mosques in the largely Shiite area of Hurriya in northwestern Baghdad. (Watch as all-out civil war threatens to overtake Iraq )
They reported people attacking Sunni houses with hand grenades and rocket-propelled grenades. Shiite militiamen are also said to have doused Sunnis with kerosene and burned them, and shot at other people.
One witness reported at least five people were killed. An official with the Association of Muslim Scholars, a Sunni group, said many more were killed and wounded but could not confirm numbers.
Iraqi Defense Ministry spokesman Mohammed al-Askari said clashes erupted between two groups in Hurriya. U.S. and Iraqi troops then arrived at the scene, set up checkpoints and restored control.
The U.S. military said it could not confirm the reports of people and mosques being torched.
In Sadr City itself, two people were hurt when U.S. helicopters fired on tents set up for funerals, police said. (Location of Sadr City)
Mourners said they were shooting weapons in the air to commemorate the dead -- not firing at the helicopters.
But the U.S. military said troops destroyed rocket launchers that had fired six rockets.
Two Sunni Arab neighborhoods -- Ghazaliya and Adhamiya -- also withstood a barrage of mortar fire that wounded 10 people earlier.
The new attacks and counterattacks threaten to bring Iraq to the brink of all-out civil war, a process that has escalated since the February bombing of a revered Shiite shrine in Samarra, north of Baghdad. Since then, thousands have fled their homes for other neighborhoods and countries in the face of Sunni-Shiite vendettas. (Watch for the divisions between Shiite and Sunni Muslims )
Thousands more have been slain. Sectarian violence has left its imprint with the daily discovery of tortured bodies around the capital despite U.S. and Iraqi military efforts to stem the brutality.
Al-Sadr bloc threatens walkout
The carnage came as anti-U.S. Shiite cleric Muqtada al-Sadr's bloc threatened to withdraw support for Iraqi Prime Minister Nuri al-Maliki should he meet President Bush as planned next week.
Such a move could jeopardize the stability of al-Maliki's administration, which has relied on the support of both the United States and fellow Shiites.
In a statement that aired on Iraqi TV, al-Sadr representative Salih al-Akeili blamed U.S.-led forces for fostering conditions that led to the massacre Thursday in Sadr City. (Watch how followers are attracted to al-Sadr's fiery anti-Americanism )
"We announce that if the security situation and the basic services do not improve, and if the prime minister goes ahead and meets with the criminal Bush in Amman, then we will suspend our memberships with the Iraqi parliament and the government," said al-Akeili, a member of al-Sadr's bloc in Iraq's parliament.
Al-Akeili said his bloc -- with 30 seats in the 275-member parliament and six Cabinet ministries -- is demanding an end to the occupation and a withdrawal from Iraq, with a timetable for such a departure.
The White House said the talks in Jordan would go forward.
"It's an outrage that these terrorists are targeting innocents in a brazen effort to topple a democratically elected government, and it is not going to work," deputy White House spokesman Scott Stanzel said. "Securing Baghdad and gaining control of the violent situation will be a priority agenda item" when Bush and Maliki meet.
Al-Maliki's office has not responded to the threat.
U.S. commanders suspect al-Sadr's militia, the Mehdi Army, has been responsible for sectarian violence against Sunnis, although the cleric has denounced such attacks.
Al-Sadr challenge to Sunni leader
Meanwhile, al-Sadr challenged a top Sunni leader -- Sheikh Hareth al-Dhari, the head of the Association of Muslim Scholars -- to take steps to end the violence, including the issuance of fatwas, or Islamic decrees.
Speaking in the southern city of Kufa, near Najaf, during prayers Friday, al-Sadr said one fatwa should "prohibit the killing of all Shiite Muslims because this will save the blood of Muslims in Iraq."
Another should prohibit people from joining al Qaeda or any party "harboring hatred against the descendants of the Prophet Mohammed."
"We condemn and denounce the blasts," he said.
Police called Thursday's strikes the worst since the war began in 2003. The Iraqi Interior Ministry imposed a curfew for Baghdad on Thursday evening. It's unclear how long the curfew will last. Baghdad International Airport also was closed till further notice.
Meanwhile, police reported a U.S. raid on al-Sadr's office in Baquba, a provincial capital northeast of Baghdad. Five people were detained, and weapons were seized. The U.S. military said it was checking the report.
Also Friday, a suicide bomber killed 22 and wounded 30 after detonating explosives strapped to his body and in a car in the northern city of Tal Afar, authorities said.
The attacker parked his vehicle, got out and set off the car bomb in a car lot before detonating himself, police said.
Tal Afar, a largely Turkmen city in Nineveh province, is about 250 miles (400 kilometers) north of Baghdad. Tal Afar has endured Sunni-Shiite sectarian fighting in the past, but it isn't clear what the motive was for Friday's attack.
In the southern city of Basra, a British soldier was shot dead Friday during a "search and detention operation," the British Defense Ministry said. The number of British military deaths in the Iraq war stands at 126.
CNN's Arwa Damon, Suzanne Malveaux, Mohammed Tawfeeq and Michael Ware contributed to this report.