They were searching a cave to recover the body of a comrade who had been shot in 2022.
Methane gas kills 12 Turkish soldiers in Iraq operation
36 minutes ago
Imogen James
BBC News

Twelve Turkish soldiers have died after being exposed to methane gas while searching a cave in Iraq, the Turkish Ministry of National Defence said.
At least 19 personnel were exposed to the gas during the search and clear operation on Sunday, and immediately taken to hospital.
By Monday 12 soldiers had died, the ministry said.
The troops were searching for the body of a soldier who was killed in gunfire in May 2022. The ministry said despite efforts the remains have still not been recovered.