Updated 1/13/2015, 4:07 p.m. EST

Some 40 people were taken to Howard University Hospital in the nation’s capital after smoke from an unidentified source filled one of Washington D.C.’s most busiest subway stations, reports say.

Authorities say the L’Enfant Plaza station was evacuated around 3:30 p.m. and at least a dozen people with injuries and one casualty was reported.

From Newser, Fire and EMS Spokeswoman Caroline Laurin confirmed that a person had died, but did not offer an official statement.

Laurin did however report that the National Transportation Safety Board (NTSB), whose office is just seconds away from the L’Enfant metro station, where at the scene and are conducting an investigation.

More on this story as it continues to develop.