By Karen Morfitt

DENVER (CBS4) – An issue with the underground train that runs from the main terminal to each of the three concourses as at Denver International airport caused 12 hours of disruption for travelers. A spokesperson for the airport says a tire blew out on one of the passenger trains, causing damage to the track and triggered a power cutoff.

(credit: Marcus Simmons)

Marcus Simmon was on the train when the trouble started around 12:30 a.m. Friday.

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“We were going kind of around a corner, and we heard two loud bangs and saw some sparks flying outside the windows,” he said.

Simmon says the smoke that followed, and a sudden stop of the train had passengers eager to get off by forcing the doors open into the underground tunnel.

“It was a very kind of scary experience. We are bundled in there, we all have our masks on, no communication with us… Do we get off do we stay on?” Simmon said.

Airport officials say fixing the track and making sure the tunnel was clear of people took hours, causing a backup of passengers trying to get to and from their gates.

“It was like a maze, I was just thinking, ‘What in the world?” one man said as he made his way out of the crowded airport.

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(credit: CBS)

There have been at least four issues with the trains in a little over a month, raising new questions about why there isn’t a second option for moving passengers.

Alex Renteria a spokesperson for the airport says when the Airport was first built there was a discussion about it.

“I believe, way in the beginning, there was an idea to do that and that and, for I believe it was for financial reasons that there was no walkway that ended up happening,” she said.

Renteria says disruptions of this size are uncommon and that the reliability of the train is just over 99%. Still, she says they are not ruling anything out.

“We are committed to exploring options to provide alternate ways to move passengers between the terminal and the consequences and improving our process when incidents like this occur,” she said.

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(credit: CBS)

Simmon, who travels on a regular basis, says changes would be welcomed, “We just seem to only have one way in and one way out.”

Karen Morfitt