TIKRIT, Iraq, May 21 (Xinhua) -- The extremist militants of the Islamic State (IS) group attacked security forces in Iraq's northern central province of Salahudin, yet leaving at least four of them killed, a provincial security source told Xinhua.
In one of the attacks, dozens of IS militants attacked security posts near the main road in north of the oil refinery town of Baiji, some 200 km north of the Iraqi capital of Baghdad, the source said on condition of anonymity.
The troops fought a fierce clash against the attackers and forced them to withdraw into the rugged desert on the provincial border between Baiji and Anbar Province, the source said.
The clashes resulted in the killing of four militants and the destruction of an IS vehicle carrying heavy machine guns, the source said.
In a separate attack, IS militants carried out an overnight assault on an outpost manned by paramilitary Hashd Shaabi units of Sunni tribes in al-Naima area in east of Salahudin's provincial capital of Tikrit, about 170 km north of Baghdad, the source added.
The attackers abducted four paramilitaries and fled the scene, according to the source.
In the morning, the security forces rushed to the scene, carried out a search operation in the area and found the body of one of the four paramilitaries with bullet holes in the head and the chest, while the other three are still missing, the source said.
The attacks came as the Iraqi security forces, backed by anti-IS international coalition, are carrying out a major offensive to drive out the IS militants from their major stronghold in the western side of Mosul in northern Iraq.