The Islamic State (IS) jihadists overnight on Saturday carried out an attack on Khabaza oilfield in Kirkuk province, a security source said.
At least two guards of the facility were killed and another was wounded, the source confirmed, noting that the casualties are all Kurdish nationals.
In the past few days, the IS sleeper cells have stepped up the attacks on the Iraqi forces and Iranian-backed Hashd al-Shaabi in and around Kirkuk.
The extremists last week deceived Hashd al-Shaabi militiamen into an ambush near Hawija, southwest of Kirkuk, and killed 27 of them.
Earlier on Friday, a raft of reports claimed that Hashd al-Shaabi militia and Iraqi federal police have withdrawn from multiple positions around Kirkuk in fear of further IS attacks. However, authorities from Baghdad refuted the reports despite a growing spread of panic among civilians in Kirkuk.