(KUNA) -- Iraqi police in Mosul said on Friday that gunmen in the northern city of Mosul had killed a Police Colonel and in the southwest city of Kirkuk police foiled a bomb attack on an oil pipeline at Biji's oil refinery. An Iraqi police source said unknown gunmen opened fire on the police chief Colonel Halab Abdulrahman while he was entering his house in the Al-Zanjili area.On a different note, a source from the Iraqi military security force protecting oil installations said that the force had foiled a bomb attack on an oil pipeline that transfers crude oil from Kirkuk to Biji's oil refinery. Armed men tried to plant explosives underneath the pipeline but fled after shots were fired from the security protection force, the source said.