Over 240 people are dead and as many as 120 workers are still trapped in a coal mine in Soma, Turkey.
Authorities said a fire began Tuesday after a transformer blew up during a shift change.
"It's too late. There's no more hope," said miner Veysel Sengul, who had already lost four friends and was waiting by the mine entrance for more.
James Stefanic helped drill the escape shaft in the rescue effort of the Chilean miners in 2010.
In that situation, Stefanic and rescue crews saved 33 men who had been trapped in the mine for 69 days.
"In this case here, where you have fire involved, it makes things a lot tougher," he said on "New Day" Wednesday.
Stefanic emphasized that the miners who may still be alive need fresh oxygen, but rescue crews should be careful not to fuel the fires that are burning underground.
He also had a message for the rescue workers in Turkey: don't stop.
"We never gave up," Stefanic said.
For updates on this story, visit CNN.com.
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