What a time for a T train to get stuck in a tunnel without air conditioning.

Around 500 MBTA riders were stuck and forced to evacuate a Blue Line train Tuesday afternoon, according to officials.

The train was disabled under the Boston Harbor between Maverick and Aquarium stations, the Boston Fire Department reported.

It took firefighters about an hour to evacuate the 500 people through the tunnel.

“They used the Nolan cart to transport anyone needing assistance using 3 exits, 2 in Boston & 1 in East Boston,” Boston Fire posted.

T passenger Shee Soto was trying to get to work when the train suddenly stopped in the tunnel. The riders were told they would be on standby for awhile until it was safe to go, but the train never went back up.

“It was getting very hot because the air conditioning was out,” Soto told the Herald at the scene.

When the riders were evacuated, they had to navigate the dark tracks and avoid wires.

“We were all sweating,” Soto said. “We were all very nervous.”

Around 2:30 p.m., officials received a report of a downed communications wire in the tunnel between Aquarium and Maverick.

The cause was under investigation, and there were no reported injuries.

“The MBTA apologizes for this disruption in Blue Line service,” a T spokesperson said in a statement. “Personnel are on site now, working to resolve the issue as quickly and safely as possible.”

A rider snapped a photo of the packed train and posted, “This is really scary.”

The train remained in the tunnel as of 5 p.m.

Shuttle buses were replacing service between Government Center and Airport. Riders were also being directed to SL3 service between Airport Station and downtown as well as to the East Boston Ferry.

The most current service information continues to be available at mbta.com/alerts and on X @ MBTA.