Perpetrators lay handmade explosives under the road where soldiers where soldiers were tasked to protect road construction crews, Hurriyet reported. Military planes patrolled the area for suspects.

The explosive, lodged in a ditch, was remotely activated. Four of the soldiers died on the spot, with another three dying at the hospital. Two were critically injured.

The PKK has been fighting an insurgency against the Turkish state since the 1980s.

Turkish President Recep Tayyip Erdogan stepped up military operations against the PKK in recent years after the collapse of a cease fire in 2015.

“We are maintaining, and will continue, our fight against terror decisively and without any delay,” Erdogan said Thursday, Sputnik News reported. “We won’t leave the blood of our martyrs and veterans on the ground.”

Meanwhile, the U.S. Embassy in Ankara condemned the attack in a twitter message. In the same message, it said, ''PKK terrorists must stop its attacks. We are together with our ally Turkey in the fight against terrorism.''

Reporter’s code: 50101