Unknown gunmen shot dead eight workers outside a power station in Baiji, some 200 km north of Baghdad, a local police source said.

"Unknown gunmen in two pickup trucks opened fire at workers of Iraq's major power station of Baiji as they were leaving the main gate of the facility, killing eight of them," the source told Xinhua on condition of anonymity.

One week ago, unknown gunmen shot dead three engineers working in the facility, he said.

Gunmen frequently attack Iraqi government employees and security forces in an attempt to cripple the U.S.-backed political process in the violence-plagued country.

Source: Xinhua