Isis in Gaza supporters protesting in May following the demolition of a mosque by Hamas.
Isis in Gaza supporters protesting in May following the demolition of a mosque by Hamas.Twitter/Isis

At least 44 people were killed on Tuesday in the US-led coalition airstrikes and clashes between Iraqi forces and Islamic State (IS) militants, security sources said.

In the northern province of Nineveh, the coalition aircraft carried out an airstrike at dawn on three vehicles carrying IS militants in Bara area near the IS-seized town of Sinjar, Luqman al-Khansouri, a leader in a Kurdish force tasked with freeing Sinjar from IS, told Xinhua.

"The airstrike resulted in destroying the three vehicles and the killing of 13 militants aboard," Khansouri said.

In Salahudin province, fierce clashes erupted between the Iraqi forces and IS militants on the main road leading to the IS-held town of Seiniyah, just west of the oil refinery town of Baiji, leaving at least 11 militants and six security members killed, a provincial security source said.

On the road to Seiniyah, the security forces have been in heavy clashes with the IS militants for two successive days as the troops and allied militias known as Hashd Shaabi, or popular mobilisation, are trying to push forward to free the town, the source said.

Meanwhile, the security forces and IS militants continued tit-for-tat clashes in the town of Baiji and the nearby oil refinery.

Also in the province, at least 150 displaced families returned to their homes in the provincial capital city of Tikrit, some 170 km north of Baghdad, about two months after the security forces and Hashd Shaabi militias freed the city from the IS militants.

Since March 2, the security forces backed by dozens of thousands of allied Shia and Sunni militias have been involved in Iraq's biggest offensive to recapture the northern part of Salahudin province, including Tikrit and other key towns and villages, from IS militants.

In Anbar province, heavy clashes erupted between IS militants and a federal police force backed by Hashd Shaabi militiamen near the militant-seized town of Garma, leaving nine policemen and militiamen killed and 15 others wounded, a provincial security source said.

In Iraq's eastern province of Diyala, a roadside bomb detonated in the morning near a school in the town of Mkheisa in northeast of the provincial capital city of Baquba, some 65 km northeast of Baghdad, leaving a teacher and four students killed and six other students wounded.

The security situation in Iraq has drastically deteriorated since June 10 last year, when bloody clashes broke out between Iraqi security forces and the IS.