Iraqi deputies have denounced the government, using a quotation from the Koran to describe Prime Minister Nouri Maliki as "depraved".
The criticism came from the bloc of MPs who support the Shia cleric Moqtada Sadr - which once backed Mr Maliki.
Iraqi troops and US-led foreign forces have been engaged in bloody battles with Mehdi Army fighters loyal to Moqtada Sadr over recent weeks.
Nine people died on Thursday in a Baghdad bomb blast aimed at US troops.
The death toll also rose in the sprawling Baghdad district of Sadr City.
In the latest violence, US forces said they had killed at least 16 militants, while heath officials said eight people had been killed overnight.
Over past weeks, more than 400 have been killed and 2,500 injured in Sadr City.