Underscoring the threat, two car bombs exploded within minutes at a mostly Shiite Baghdad market, killing at least nine soldiers and a civilian in a rash of attacks many here worry could deepen the conflict beyond the deadly insurgency against US forces and their Iraqi allies.
With the body count rising, an influential association of Sunni clerics accused the government's Shia-dominated security forces of participating in the carnage --a claim rejected by the Sunni defense minister and other government officials.
"The new government will strike with an iron fist against any criminal who tries to harm a Sunni or a Shiite citizen," Prime Minister Ibrahim al-Jaafari told reporters after visiting Iraq's top Shiite cleric in the holy city of Najaf. "The death sentence will be implemented."
The Shia premier has sought to reach out to the disaffected Sunni Arab minority --believed to be driving the insurgency -- by including them in his new government announced April 28. But Sunnis are still underrepresented in Cabinet and a newly appointed committee tasked with drafting a new constitution by August 15.
Returning from a one-day trip to meet Iraq's new leaders, Secretary of State Condoleezza Rice praised the expanded role given Sunni Arabs and said she was confident the Iraqi government could meet important deadlines.
At the same time, she blamed Syria for complicating the new Iraqi government's efforts to quell violence.
The US military contends Iraq's remote desert region near Syria is a haven for foreign combatants who cross the frontier along ancient smuggling routes and collect weapons to use in some of Iraq's deadliest attacks. US forces conducted a major campaign to clear the area last week.
Two car bombs at the Baghdad market went off in quick succession, killing the nine soldiers and a civilian. The second blast targeted soldiers who rushed to help the victims of the first explosion.
Shop keepers piled the injured into pickup trucks to help get them to hospital. Yarmouk Hospital treated 29 people injured in the blasts, one of whom died of his injuries.
Radical Shiite cleric Muqtada al-Sadr also came out of hiding Monday for the first time since his fighters clashed with American forces in Najaf and Baghdad in August.
Al-Sadr held a news conference demanding that US-led forces leave Iraq and Saddam Hussein be punished. "I want the immediate withdrawal of the occupation forces," he said. More than 490 Iraqis have been killed in a series of car bombings, ambushes and other insurgent attacks since Iraq's first democratically elected government was formed.
In a grisly twist to the relentless violence, batches of bodies, many of them bound and blindfolded, turned up
Thirteen were found in a garbage-strewn lot in Baghdad's Shiite-dominated Sadr City slum, 11 more in an abandoned chicken farm south of the capital in an insurgent stronghold dubbed Iraq's Triangle of Death, and 10 identified as Iraqi soldiers in the battleground city of Ramadi.
Late Sunday, at least eight more men were found near a dam in another Shiite-dominated Baghdad neighborhood, their hands tied behind their backs and bullet wounds to their heads. Two of the victims were still alive, but died soon afterward, police said.
Associated Press Television News footage showed the blood-soaked ground where the bodies were found, and three of the corpses being brought into a Baghdad hospital. The Sunni-based Association of Muslim Scholars said the two survivors told their families before they died that security force members seized them from mosques and shot them.
Defense Minister Saadoun al-Duleimi denied the accusation, saying the killings were carried out by "terrorists" wearing military uniforms. But in a gesture to the association, he said Iraqi security forces would be banned from entering places of worship and universities.
US forces say they have repeatedly been attacked from inside mosques. They rely on their Iraqi counterparts to conduct searches there to avoid provoking Iraqis. Another body was also found Monday, this time an Iraqi Kurd shot in the head and chest and left in a garbage dump in Kirkuk, 180 miles north of Baghdad, police and witnesses said. An AP reporter saw the victim, identified by police as Najat Saadoun, with his hands tied behind his back.
Al-Jaafari spokesman Laith Kuba said such attacks "aim to create sectarian fighting in the country because such clashes could bring more recruits to (militant) groups."
"The government is aware of that and will not let this plan succeed," Kuba told The Associated Press.
Grand Ayatollah Ali al-Sistani also stressed the need for "fighting terrorism and guaranteeing security," during his meeting with al-Jaafari, said an aide to the cleric, speaking on condition of anonymity. But he urged his Shiite followers to exercise restraint in the face of provocative attacks, the aide said.
There are other reasons why some of the victims may have been killed. Insurgents regularly target Iraqi security forces, government officials and others deemed to be collaborating with US-led forces in the country. Others are kidnapped and killed in attempts to extort lucrative ransoms.
But there have also been a steady stream of retaliatory attacks between armed Sunni and Shiite groups in parts of Iraq. Recently, they have included major bombings at mosques, markets and funerals frequented by Shiites and their Kurdish allies now in power.
(Associated Press writers Omar Sinan and Qassim Abdul-Zahara contributed to this report in Baghdad.)