Iraqi police have found 27 bodies with gunshot wounds in southeast Baghdad, raising the number of victims of killings in the capital since Monday morning to at least 80.
Police said they appeared to have been killed in the last few days.
Earlier, the bodies of 15 men were found in west Baghdad.
They were in an abandoned vehicle with their hands and feet bound and showing signs of torture.
That discovery was made not far from where the bodies of 18 men killed in similar fashion were found in a minibus a week ago.
Many of those were identified as Sunni Muslims, fuelling accusations Shia militias are running death squads against the minority.
Bush in claims on Iran devices
Separately, US President George W Bush has renewed allegations that Iranians are helping to arm militants in Iraq.
Mr Bush said there was no doubt they were assisting insurgents to make bombs used in attacks on American-led forces.
He said that among the thousands of improvised devices found and dealt with in Iraq in recent months, some of the most powerful had components that clearly originated in Iran.
