WASHINGTON: A woman died and dozens of people were injured after thick smoke filled a subway tunnel in the US capital Monday during the evening rush hour, officials said. A spokeswoman for the Washington Metropolitan Area Transit Authority (WMATA) confirmed the incident, which caused mayhem in the second-busiest US mass transit system after New York.

Washington Emergency Medical Services said that 84 people were taken to the hospital with “various injuries” and that one firefighter was also injured. Some 200 people were being evaluated, it added. The Washington Post reported two people were suffering from critical injuries.

WMATA said emergency crews were deployed and that the station was being aired out.

Smoke filled the L’Enfant Plaza subway station in the center of the city during rush hour, prompting the evacuation of startled passengers and forcing commuters to find other ways to get home after work. The train was bound for Virginia across the Potomac River.

Emergency workers escorted smoke inhalation victims to medical aid buses to receive oxygen.