Five other peshmerga fighters were wounded in the violence late Sunday in northern Iraq that targeted an outpost north of Kirkuk, the source said.

Kurdish army forces confirmed the deadly attack but did not say how peshmerga fighters were killed in wounded, in a statement accusing IS of responsibility.

It was the third attack blamed on IS jihadists in less than two weeks against the Kurdish fighters in northern Iraq.

On Thursday, IS claimed responsibility for an assault south of the Kurdish capital of Arbil that killed at least nine peshmerga fighters and three civilians.

At the end of November, five peshmergas were killed in a roadside bombing also claimed by the jihadist group.

IS seized swathes of Iraq in a lightning offensive in 2014, before being beaten back by a counter-insurgency campaign supported by a US-led military coalition.

The Iraqi government declared the Sunni extremists defeated in late 2017, although the IS retains sleeper cells which still strike security forces with hit-and-run attacks.