A microphone lowered into a narrow hole drilled into a mine cavity where six workers are believed to be trapped has detected no sound so far, officials said early Friday.

A TV news crew reports near a sign of support outside the community center where miners’ families are gathered.

There has been no communication with the six men since Monday’s mine collapse.

The 2.5 inch bore hole reached the cavity in the central Utah mine more than 1,800 feet below the surface at about 10 p.m. MT Thursday (midnight ET), according to Richard Stickler, assistant secretary of the Department of Labor for mine safety and health.

Mine CEO Bob Murray said no conclusions could be drawn yet from the lack of sound detected.

“The fact that we have not picked up any sound I believe should not be interpreted as bad news,” Murray said. He said the “good news” is that the drill found the cavity.

“There could be a number of factors as to why sounds in there might not be picked up, and I wouldn’t look at it as good or bad news,” he said.

One encouraging sign, he added, was testing showed that the air in the cavity was “very, very good.”

“That means that if they’re alive, they’re going to stay alive in that atmosphere,” Murray said.

Murray and Stickler spoke to reporters at the rescue command center early Friday morning. Murray said they met first with the families of the miners, describing their reaction to the news as “quiet” and “subdued.”

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