TIKRIT Iraq - Iraq's biggest oil refinery was shut down overnight and its foreign staff evacuated, officials told Reuters on Tuesday.
Local staff remained in place and the military was in control of the Baiji facility.
Militants from al Qaeda splinter group Islamic State of Iraq and al-Sham (ISIS) seized Iraq's second-biggest city of Mosul last week and other Sunni armed groups advanced into the town of Baiji and surrounded its refinery.
Baiji is one of three oil refineries in Iraq and only processes oil from the north. The other two are located in Baghdad and the south and are firmly under government control and operational.
“Due to the recent attacks of militants by mortars, the refinery administration decided to evacuate foreign workers for their safety and also to completely shut down production units to avoid extensive damage that could result," a chief engineer at the refinery said on condition of anonymity.