Saboteurs have bombed two oil pipelines transporting crude from northern and eastern Iraq to Baghdad's Dora refinery, officials said on Saturday. Major Ali Mahmoud said National Guard forces were trying to extinguish a fire which damaged 150 metres (yards) of the Khana pipeline northeast of Baghdad. He said another bomb was found on Saturday along the same line and was safely defused. An official said saboteurs on Friday blew up a section of another oil pipeline in the Mashahdeh area, some 50 km (30 miles) north of Baghdad. The pipeline also feeds the Dora refinery, which processes 110,000 barrels per day (bpd). Officials would not say if the attacks disrupted the flow of oil but neither pipeline involves exports. Guerrilla attacks on Iraq's oil pipelines have disrupted refinery operations and cost the U.S.-backed interim government billions of dollars, including lost oil export proceeds and around $200 million a month worth of refined product imports. Saboteurs hit a section of the northern oil export network on Thursday. Oil officials said crude kept flowing normally through alternative pipelines to Turkey's Ceyhan port at 300,000 bpd. Iraq exports another 1.6 million bpd through two southern offshore terminals in the Gulf and the flows had been normal for around two months, the officials said.