KIRKUK, Kurdistan Region—Shiite militias have killed 15 members of the Qaragholi tribe near Tikrit and taken dozens more captive, a tribal leader said on Wednesday.

Mahmoud Abd, a Qaragholi tribal chief told the media that Shiite militias had attacked the Sunni tribe in Salahaddin province and killed 15 people, took 50 more captive and burnt more than 400 homes.

“The perpetrators were Shiite militias, but the motive behind the attack isn’t clear,” said Abd.

The Sunni tribal chief said that many of the wounded were left for dead on the streets.

In recent weeks international human rights organizations have reported massacres carried out by the Shiite militia against civilian Sunnis in Salahaddin and Diyala provinces where the Islamic State (ISIS) and the government are battling for control.