Kurdish troops have freed 15 oil workers seized by the Islamic State (IS) militants a few days back at an oil facility near the city of Kirkuk in northern Iraq, a security source said Sunday.

"The 15 workers, who are affiliated to the Iraqi North Oil Company, were found held in a cellar at the sprawling facility after the Peshmerga (Kurdish troops) defeated the IS militants," Rasoul Qader, a Peshmerga leader in Kirkuk, said without giving further details, according to a Xinhua report.

The workers were captured Friday when IS militants attacked the oil facility of Khubbaz, about 25 km southwest of Kirkuk, which itself is located about 250 km north of the Iraqi capital of Baghdad.

The Kurdish troops were clearing the buildings of the Khubbaz oil facility of the dozens of bombs that were planted by the IS militants before they withdrew from the facility earlier, the source said.

In a separate incident, a Peshmerga member was killed and three others were injured Sunday when a booby-trapped hummer truck left at the oil facility detonated, a Peshmerga source told Xinhua on the condition of anonymity.

Meanwhile, two roadside bombs went off near a Shia militia convoy in the Taji area, about 15 km north of Baghdad, leaving a militiaman killed and 15 others injured, a local police source told Xinhua.

The security situation in Iraq began to drastically deteriorate from June 10, last year, when bloody clashes broke out between the Iraqi security forces and the IS, which took control of the country's northern province of Nineveh and later seized swathes of territories after Iraqi forces abandoned their posts in other predominantly Sunni provinces.