Four civilians were killed after PKK terrorists detonated a roadside bomb as a truck carrying workers and fuel passed by in Turkey’s southeastern Şırnak province on Wednesday, the governor’s office said.

The explosion took place in Kürtik Tepe area in the Silopi district at 18:35 local time.

The vehicle was carrying fuel and workers for the road construction site between the Görümlü town and Mount Judi, Şırnak Governor’s Office said in a statement.

All four people on the vehicle were killed in the explosion, the statement said, adding that an investigation has been launched into the incident.

The deceased workers were identified as Emin Eroğlu, Hacı Atilla, Nesim Bestaş and Osman Tuncay. Their bodies were sent to Şırnak State Hospital for an autopsy and will be buried in the Güçlükonak district after procedures.

In its more than 30-year terror campaign against Turkey, the PKK – listed as a terrorist organization by Turkey, the U.S. and the EU – has been responsible for the deaths of nearly 40,000 people, including many women, children and infants.

Military operations, including Operation Claw in northern Iraq and Operation Kıran in Turkey, continue to eliminate the presence of PKK terrorists threatening national security within the country and near its borders.

Turkish security forces regularly conduct counterterrorism operations in the eastern and southeastern provinces of Turkey where the PKK has attempted to establish a strong presence. The Turkish Armed Forces (TSK) also carry out cross-border operations in northern Iraq, a region where PKK terrorists have hideouts and bases from which to carry out attacks on Turkey, with particular attention to targeting high-level terrorists.