A war of words has erupted over a raid by Iraqi and US forces on a Baghdad prayer complex that left about 20 dead.
The US said the raid was carried out by Iraqi commandos with US Special Forces only in an advisory role
The room in Sadr City where the deaths occurred appeared to be a prayer hall but the US military said it had not been identified as a mosque.
Iraq's interior minister said entering the complex and carrying out the killings was an "unjustified and flagrant attack".
Shia politicians say US and Iraqi forces tied up worshippers and shot them. The US military denied the claims.
The Shias say those who died were worshippers - the US military said 16 insurgents had been killed.
As relatives buried the dead, interim Prime Minister Ibrahim al-Jaafari expressed "deep concern" and sought a US inquiry.
Iraqis in the Shia neighbourhood where the deaths occurred carried flags at a mock funeral parade for the victims.