TIKRIT, Iraq, June 2 (Xinhua) -- Four Iraqi policemen were killed Saturday in a bomb explosion in Iraq's central province of Salahudin, a provincial police source told Xinhua.
The incident occurred in early morning when a roadside bomb struck a police patrol at a village near the city of Shirqat, some 280 km north of the Iraqi capital Baghdad, destroying a police vehicle and killing four policemen aboard, Colonel Mohammed al-Jubouri said.
Iraqi security forces launched investigation into the incident and carried out a search operation in the area looking for the attackers, Jubouri added.
No group has so far claimed responsible for the attack, which came despite repeated operations by the Iraqi security forces to clear the areas around Shirqat from the remnants of the extremists Islamic State (IS) militants.
Earlier, hundreds of IS militants fled their former bases in the key cities of Salahudin province, including the provincial capital Tikrit, some 170 km north of Baghdad, after the Iraqi forces cleared these areas during major anti-IS offensives.
Late in 2017, Iraqi Prime Minister Haider al-Abadi, also the Commander-in-Chief of Iraqi forces, officially declared full liberation of Iraq from IS militants after Iraqi forces recaptured all the areas once seized by the extremist group.
However, remnants of IS militants melted in urban areas or resorted to deserts and rugged areas in northern and eastern parts of Salahudin province as well as in the nearby Himreen mountainous area, and are carrying out almost daily attacks against civilians and Iraqi forces.