Violence mostly targeting Sunnis in Baghdad and west Iraq left 13 people dead on Saturday, including five worshippers killed by gunmen at a mosque, the latest in spiralling violence.
The surge in unrest, which has left more than 3,800 people dead so far this year, has sparked fears of a return to the all-out sectarian bloodshed that blighted Iraq in 2006 and 2007.
In Baghdad, gunmen shot dead five people at a Sunni mosque during early morning prayers in the predominantly-Shiite neighbourhood of Baghdad Jadidha, in the capital's east, two security officials said.
One worshipper was wounded in the shooting. A medical source confirmed the toll.
West of Baghdad in the mostly-Sunni city of Ramadi, meanwhile, a suicide bomber blew himself up against a police patrol in the centre of the city, killing five people, including a lieutenant colonel, police and medical sources said.
Eight others were wounded in the blast in the city, which is the capital of the western province of Anbar.
And just north of Baghdad, one Sunni anti-Al-Qaeda militiaman was killed and four others wounded in a bombing.
Though most of Saturday's violence targeted Sunnis, a bombing at a farm in the Shiite city of Dujail killed two teenage girls and wounded two men.
The attacks came despite security operations targeting militants in Baghdad and to the north and west, though the government has faced charges of not dealing with the root causes of the country's worst violence since 2008.
The surge in bloodletting has coincided with demonstrations by the Sunni Arab minority against alleged ill treatment at the hands of the Shiite-led government and security forces.