North Oil Co., a state-owned Iraqi company which oversees oil fields in the north of the country has confirmed that the facility, which is located near the northern Iraqi city of Kirkuk, has been taken and that its 15 employees are still unaccounted for.
"We received a call from one of the workers saying dozens of Daesh fighters were surrounding the facility and asking workers to leave the premises. We lost contact and now the workers might be taken hostage," the agency quotes an engineer from North Oil Co as saying.
Islamic State insurgents attacked regional Kurdish forces southwest of Kirkuk on Friday, seizing some areas including parts of the Khabbaz oilfields.
Kurdish peshmerga forces sought to push back Islamic State militants in further fighting near Khabbaz on Saturday, Kurdish military sources told Reuters.
According to Al Jazeera, the peshemerga fighters managed to rebuff IS militants trying to occupy the oil-producing city of Kirkuk.
On Friday, the IS extremist group launched a major attack in Kirkuk, killing a top commander of the Iraqi Kurdistan Peshmerga fighters, Brig. Gen. Shirko Fatih, and more than 25 of his soldiers.
The Islamic State seized at least four small oilfields when it overran large areas of northern Iraq last summer, and began selling crude oil and gasoline to finance their operations.