Two officers and one civilian were killed when a car bomb exploded outside a police station near Turkey’s southeastern city of Diyarbakir on Monday, in an attack suspected to have been carried out by Kurdish militants, security sources said.

Ambulances rushed to the scene, Dogan News Agency said. The area where the explosion hit is on a road between Diyarbakir and the district of Bismil, about 50 kilometers (31 miles) east, the security sources said.

Footage on Turkey’s CNN Turk television showed the blast left the building’s concrete frame and twisted metal exposed with the windows entirely blown out and its roof partially collapsed. The explosion left a crater on the ground.

Turkey’s southeast has seen some of the most intense fighting in decades after a ceasefire between the Turkish state and the outlawed Kurdistan Workers Party (PKK) collapsed in July 2015. Thousands of militants, security force members and civilians have since been killed in fighting across the region.

Monday is the anniversary of autonomy-seeking PKK, designated a terrorist group by Turkey, the European Union and the United States, taking up arms against the Turkish state in 1984. More than 40,000 people have been killed in the conflict.

(Reporting by Seyhmus Cakan; Writing by Humeyra Pamuk; Editing by David Dolan and Patrick Markey)