ISTANBUL — An explosion on Tuesday in a coal mine in western Turkey killed more than 200 miners and left hundreds of others trapped underground, Turkey’s energy minister said early Wednesday.

The official, Taner Yildiz, said many, and perhaps most, of the miners had died of smoke inhalation. “We’re dealing with carbon monoxide and carbon dioxide poisoning,” Mr. Yildiz said on television. Rescue efforts were continuing but “time is against us,” he added.

The explosion set off a fire that blocked exits from the mine, Cengiz Ergun, the mayor of the town of Manisa, said in a telephone interview with CNN Turk news television. The area has some of the world’s largest coal reserves.

Image An injured miner was carried away by rescuers. The explosion took place as workers were changing shifts in midafternoon. “Time is against us,” an official said of the workers trapped underground. Credit... Bulent Kilic/Agence France-Presse — Getty Images

It took place as workers were changing shifts in midafternoon, which made it more difficult for officials to determine how many miners were trapped. As many as 250 could still be trapped as far as 2,000 feet below the surface, several local officials said.