An MBTA spokesperson said the train operator stopped the train after they spotted a downed wire in the tunnel.

An old and neglected piece of equipment caused the issue that led to a Blue Line train being stopped in a tunnel, MBTA general manager Phil Eng said.

A communication wire issue led to the evacuation of about 465 passengers from a Blue Line MBTA train in Boston.

A signal problem at an MBTA station in Boston halted Blue Line services on Tuesday, prompting shuttle buses to be used to replace train services.

Shuttle buses are replacing a portion of the Blue Line due to a signal issue at the Aquarium station, the MBTA said Tuesday.

MBTA Blue Line trains were being held in Boston and buses brought in to replace service because of a signal problem near Long Wharf on Tuesday. The issue was near Aquarium Station, the transit agency said,