Baghdad, Jan 25 : Four Iraqi soldiers were killed in a roadside bomb explosion in the northern province of Kirkuk, a provincial security source said. The explosion took place on Monday when the soldiers were carrying out an operation to hunt down the militants of the extremist Islamic State (IS) group in Wadi al-Shay, a rugged area in southern Kirkuk, Abbas al-Obaidi told Xinhua. The explosion resulted in the killing of four soldiers and the destruction of their military vehicle, al-Obaidi said, adding a reinforcement security force rushed to the scene after the explosion, Xinhua news agency reported. The provinces, which the IS militants had previously controlled, have witnessed their intense activities during the past months, despite repeated military operations to hunt them down. The security situation in Iraq has been improving since the Iraqi forces defeated the IS in 2017. However, IS remnants have since melted into urban centers, deserts, and rugged areas, carrying out frequent guerilla attacks against security forces and civilians. /IANS