In the latest sign of rising sectarian tensions, Harith al-Dhari, the head of the influential Association of Muslim Scholars (AMS), on Tuesday blamed the Badr Brigades for the recent spate of killings of Sunni clerics in the country.
"The parties that are behind the campaign of killings of preachers of mosques and worshippers are ... the Badr Brigades," al-Dhari said.
"Badr forces are responsible for the escalating tensions," he said.
Badr Brigades is the armed wing of the Supreme Council of the Islamic Revolution in Iraq.
The AMS called for a three-day closure of Sunni mosques in protest at the killings.
A senior Badr official, Hadi al-Amiri, denied the accusations.
The recent spate of killings has
stoked sectarian tensions
"I consider these comments from al-Dhari to be irresponsible and only serve to pour fuel on the flames. It does not benefit the stability of Iraq's security in any way," he said.
"We Iraqis, Sunnis and Shias, should all stand against terrorism and against anyone who wants to draw us into a sectarian battle."
Al-Dhari, however, said Sunnis would not keep silent over the killings.
"We are heading towards a catastrophe, only God knows when it will end, this is a warning from us," he said.
The Badr Brigades spent many years in exile in Iran during
Saddam' Hussein's rule. They returned to Iraq after Hussein was toppled in 2003.
Against this backdrop of rising sectarian tensions, Iraq witnessed more violence during the day.
Drive-by shooters have killed a senior member of Iraq's Interior Ministry, escalating a campaign against the new government's administration and security infrastructure.
"The parties that are behind the campaign of killings of preachers of mosques and worshippers are the
Association of Muslim Scholars head
Police Brigadier-General Ibrahim Khamas was shot and killed in his car by four armed men driving in a four-door sedan as he drove through Baghdad's south-eastern Zaafaraniyah district on Wednesday, police Colonel Nouri Abdullah said.
Khamas' wife and driver were injured in the attack, he added.
The killing was purportedly claimed by al-Qaida in Iraq, the group run by Jordanian Abu Musab al-Zarqawi. A statement posted on an internet site described Khamas as "one of the heads of apostasy, and one of America's tails."
The authenticity of the claim, posted on a site that carries similar statements, could not be verified.
In other developments, a
car bomb detonated in Baquba, 60km northeast of Baghdad, injuring 18 people - including 14 police officers.
The car, parked in central Baquba, blew up as a three-car police convoy drove by, damaging all the vehicles, police Colonel Mudhafar Muhammed said.
In the northern city of Kirkuk, Iraqi police found the dead bodies of seven Iraqis working for a security company. The seven are believed to be Turkmen from the town, Aljazeera reports.
The car bomb in Baquba injured
14 people on Wednesday
In Baghdad, a roadside bomb targeting a US military convoy driving through the eastern part of the city injured seven Iraqis, police Lieutenant-Colonel Ahmed Aboud Efait said.
There were no reports of any Americans injured, he added.
Armed men also shot dead a Transport Ministry driver, Ali Mutib Sakr, in Sadr City, a predominantly Shia area in the eastern part of the capital, police Lieutenant-Colonel Shakir Wadi said.
And Iraq's Central Criminal Court, in Baghdad, sentenced an Iraqi man to life in prison for the illegal possession of 400 rockets, Aljazeera reports.
Two Iraqi police officers were killed in a car bomb attack near the oil refinery town of Baiji.
The bomb targeted a US-Iraqi convoy about 3am (2300 GMT) on Wednesday, on the road near Siniya, 200km north of Baghdad, Ali Yusuf, a police captain said.
A surge in violence against mostly Iraqi police and army targets has killed nearly 500 people since the start of May, as the country's government struggles to quell a raging uprising.
Mortar attacks by fighters in northern Mosul on Wednesday killed two Iraqis and injured eight others, including seven schoolchildren, police and hospital officials said.
US soldiers and Iraq police at the
car-bombing site in Baquba
Four of the rounds hit the city's police academy, but caused no injuries, police Brigadier-General Wathiq Mohammed said.
One round landed in front of a grocer's shop in the al-Masarif neighbourhood and killed the owner, Dr Bahaa-Eddine al-Bakri, of the Jamhuri Teaching Hospital, said.
Another struck a car and killed its driver, al-Bakri said, while seven children walking to school in the al-Jamaa neighbourhood were injured by another.
All of the attacks occurred in eastern Mosul.
Mosul, 360km northwest of Baghdad, is Iraq's third largest city and has in recent months been beset by organised attacks and dozens of car bombs.