"We can't give any information on the casualties right now," Kucuk said. "There are several people under the debris."
Rescue workers were on their way to the mine, 20 kilometers (12 miles) from the center of Dursunbey, Kucuk said.
In December, a similar accident killed 19 miners in Bursa province, also in northwestern Turkey. Safety violations and outdated equipment have been factors in past mine accidents in the country.
In Turkey's worst mining disaster, a gas explosion killed 270 workers near the Black Sea port of Zonguldak in 1992.
