Four pro-government fighters were killed by a roadside bomb on Tuesday near Tal Afar city in northern Iraq, according to an Iraqi military officer.
The device struck a vehicle carrying fighters from the Shia Hashd al-Shaabi militia near the city, Mohammed al-Shufani told Anadolu Agency.
"All the fighters aboard the vehicle were killed in the blast," he said.
Though there was no claim of responsibility for the bombing, Iraqi authorities often blame the Daesh terrorist group for such attacks.
Daesh has captured the predominantly Turkmen city in mid-2014.
Last month, Iraqi Prime Minister Haider al-Abadi vowed to launch a military offensive to capture Tal Afar from Daesh.
On Monday, al-Abadi formally declared victory against Daesh in Mosul, which was overrun by the terrorist group in 2014.
Reporting by Mohammed Walid; Writing by Ali Abo Rezeg