The National Transportation Safety Board (NTSB) held an investigative hearing open to the public in the NTSB Boardroom. During the hearing, the NTSB gathered sworn testimonies about the Jan. 12, 2015, Washington Metropolitan Area Transit Authority (WMATA) southbound Yellow Line train 302, with about 380 passengers on board, stopped after encountering heavy smoke in the tunnel between the L’Enfant Plaza station and the Potomac River bridge in Washington, DC. It is a fact-finding step in the safety investigation and the testimonies will become part of the public record.
Read more:
https://www.ntsb.gov/investigations/Pages/DCA15FR004.aspx