Twelve Turkish soldiers died after being exposed to methane gas during a search operation in a cave in northern Iraq, the defence ministry said on Monday.
In a statement, the ministry said the incident took place on Sunday during a mission to locate the remains of a Turkish soldier killed during a military operation against the outlawed Kurdistan Workers Party (PKK).
Other soldiers also exposed to the gas in the cave have been taken to the hospital for treatment, the ministry said.
The incident comes at a sensitive time, with Turkiye in talks to end the conflict with the Kurds after the PKK militant group agreed to halt its decades-long armed struggle.
The conflict, which began in 1984, has cost more than 40,000 lives.
It did not explain the origin of the methane gas in the caves.
“During a search operation in a cave… previously known to have been used as a hospital… 19 of our personnel were exposed to methane gas,” it had said on Sunday.
It did not give any information about the condition of the other seven soldiers who were exposed to the gas, but said a farewell ceremony for the 12 victims was held at an airport in southeastern Turkiye.
The soldier whose body they were searching for was killed as Turkish troops were conducting Operation Claw Lock, a four-month sweep that began in April 2022 to root out Kurdish PKK militants holed up in caves along the border.
The methane incident occurred on Sunday as a delegation from the pro-Kurdish DEM party was meeting jailed PKK founder Abdullah Ocalan, who — in a rare move — extended his condolences over the deaths.
“This incident caused Mr Ocalan and all of us deep sadness,” a delegation statement said, offering condolences “to their families and relatives”.
— With additional input from AFP
