One killed as Washington subway train abruptly stops, goes dark and fills with smoke

A woman riding on a Washington Metro train died and 83 other passengers were taken to hospital, at least two in critical condition, after the train abruptly stopped in a tunnel, went dark and filled with smoke following an electrical fault, authorities said.

Scores of riders were aboard the Virginia-bound Yellow Line train, which had just left the L'Enfant Plaza station in Washington, when it came to a halt about 50 metres into the tunnel on Monday, according to Metro officials.

Passengers said the darkened cars quickly filled with smoke. Several riders said as much as an hour went by before firefighters arrived and led them out of the cars, escorting them back to the station. In the meantime, while the passengers waited in the smoke-filled cars, many were choking and some lost consciousness, witnesses said.

NTSB investigator Michael Flanigon said an electrical "arcing" involving the high-voltage third rail led the train to stop and quickly filled the tunnel with smoke. An arcing occurs when electricity from the third rail comes into contact with another substance that conducts electricity, such as water.

Flanigon said the cause of the arcing was not yet known but an investigation was ongoing.

Metro General Manager Richard Sarles, said "We have one fatality, a woman who was in distress on the train, which I'm very sorry to report," said Sarles, his voice sombre. "And my heart goes out to her family."

The situation began to unfold shortly before 3.30pm Eugene Jones, the interim chief of the Washington Fire and Emergency Medical Services, said. Firefighters did not immediately enter the tunnel to help the riders because they were not sure whether the subway's electrified third rail had been deactivated. But Jones said the delay was "nothing like" the length of time described by passengers.