More than 450 MBTA passengers were evacuated from a Blue Line train in the tunnel under the Boston Harbor due to a signal issue Tuesday afternoon. 

The MBTA later said it was caused by a downed communication line between the Maverick and Aquarium stations at about 2:30 p.m. MBTA General Manager Phillip Eng said the cable that came down was 50 years old.

"Last night the teams went in, they made interim repairs to the cable, they spliced some, we removed some," Eng told reporters Wednesday. "But while we were in there, we also saw that there's other areas of cable that we want to proactively address. And what we're going to do is go back in over the next few nights and permanently replace significant sections of this cable." 

"As we were passing another train there was a bright flash of light," passenger Jadan Wenceslao said Tuesday. "Lots of like scraping noises. Then you could see a cable that goes along the top of the train it's just hanging off the side of the window." 

Passengers walk along tracks

Passengers on the train were stuck on board for nearly two hours and then had to walk through the tunnel to an emergency exit. 

"They had us walk out the back, and then we walked down the tracks," passenger Hayden Green said. 

Boston firefighters, EMS and Transit Police escorted approximately 465 riders off the train. No injuries were reported, according to the MBTA. 

Shuttle buses replaced service between the airport and Government Center. Regular service resumed at about 8:30 p.m. Tuesday. 

Passengers described a stressful and dark journey through the tunnel. 

"I was pretty nervous because it all went dark, it was pretty hot," said passenger Sage Soto. "I had to get to work so I was real stressed about that too and it took us almost like two hours for us to leave the train." 

The MBTA issued a statement apologizing for the delays.

• MBTA