A senior Sunni leader in Iraq has accused the militia of an influential Shia party of killing Sunni clerics.
Mr Dhari's accusations add fuel to the sectarian conflict, say observers
Harith al-Dhari, head of the Sunni Muslim Clerics Association, said the Badr Brigades were behind the murders.
He said the group - linked to the Supreme Council of the Islamic Revolution in Iraq - was fuelling the escalating sectarian violence.
The Badr Brigades denied the accusations and said all Iraqis should stand firm against sectarianism.
"I declared previously that we knew the parties standing behind those assassinations conducted against the imams, preachers and worshippers," Mr al-Dhari told a news conference on Wednesday.
"We will uncover this party for you - it is the Badr Brigades."
Mr al-Dhari's declaration comes in the wake of a wave of violence that observers say seems to be aimed at sparking a conflict between Sunni and Shia Muslims.
On Tuesday in Baghdad, a Shia cleric was shot dead, and police found the bodies of two Sunni clerics who had been kidnapped from mosques several days earlier.
In recent weeks, police have found dozens of bodies, mostly Shia but some Sunni, dumped in various locations, apparently shot execution-style - which has raised fears that the violence could develop into a civil war.
Correspondents say the tit-for-tat killings of clerics suggests some Shia groups are ignoring their leaders' call for restraint in the face of the insurgency.
Hadi al-Amri, general secretary of the Badr Brigades, denied the charge and accused the Sunni association of encouraging sectarian violence.
"These accusations aim to push Iraq into a sectarian conflict," he told AP news agency.
"We condemn all these terrorist operations, and we also condemn and denounce all these irresponsible declarations, we consider that these declarations encourage terrorism and justify the bloodshed in Iraq."
Iraqi Prime Minister Ibrahim al-Jaafari has vowed to strike against anyone trying to foment violence between the country's Shia and Sunni communities.