Four Iraqi journalists were killed when gunmen opened fire on their car near the northern city of Kirkuk.
One of the journalists was said to be the director of a local media organisation which publishes several newspapers.
US Vice President Dick Cheney met Iraqi leaders this morning during a previously unannounced visit to Baghdad.
He was expected to press for more progress in meeting political benchmarks aimed at ending sectarian violence.
Earlier, a truck bomb killed 12 people and wounded 53 in the northern city of Arbil.
And the US military confirmed that an attack helicopter killed five bystanders including two children when it fired on insurgents north of Baghdad yesterday.
Lt-Col Mike Donnelly denied media reports that the helicopter had fired on a school.
He said an investigation had been opened into how the civilians could have been killed near the town of Mandali in Diyala province.
Iraqi police Captain Ayad Hussein had earlier told reporters that 'seven students' were killed when Mandali's Al-Saada primary school was fired on by Apache helicopter gunships.
