A coal mine explosion in western Turkey has killed four workers and left approximately 300 trapped.
The four people "died of choking and burns," said local MP Muzaffer Yurttas.
It is estimated that 850 people were underground when the explosion occurred.
Energy Ministry Taner Yildiz is heading to Manisa to oversee the rescue operation where four teams are working on releasing the 300 workers trapped 2km below from the surface.
"Various numbers can be reported. I don't want to give any numbers. We first have to reach our workers underground," he told journalists.
The chief of the mining trade union for the Manisa province told state news agency Anadolu that fresh air was being pumped into the mine to aid those still trapped.
The town of Soma lies 150km south of Istanbul.
Mining accidents are not uncommon in Turkey due to poor safety conditions for workers.
The worst industrial disaster in Turkish history was a 1992 gas explosion near the Black Sea port of Zonguldak which killed 270 workers.