Six Turkish miners were killed when an unlicensed coal mine collapsed on Tuesday in the southeastern province of Sirnak, the country's emergencies agency said.
Search and rescue teams were at the scene of the accident, the Disaster and Emergency Management Authority (AFAD) said in a statement.
Two workers were injured and taken to hospital, state-run news agency Anadolu said.
The energy ministry was quoted by local media as saying that the mine was working without a licence after it was shut down in 2013 because of security risks.
The accident comes more than three years after the country's worst modern industrial disaster -- 301 miners were killed in May 2014 following a fire at the Soma mine in western Turkey.
Turkish officials admit the country has shortcomings in industrial safety but legislation had been tightened since the Soma disaster, which sparked anger against the government led by then-premier Recep Tayyip Erdogan, now president.