BART's 24th Street Mission station in San Francisco was closed Thursday evening due to a major medical emergency, BART officials said.
As of 6:37 p.m. BART was evacuating the station and the station was closed.
BART officials said to expect major delays.
BART officials said San Francisco Municipal Railway buses are offering service to BART riders affected by the closure.
As of 7:03 p.m. BART passengers can ride Muni bus Nos. 14 and 14R at 24th Street. The buses run between BART's Embarcadero station and Daly City.
BART officials said the system is experiencing delays at San Francisco stations in the Daly City, Millbrae and San Francisco International Airport directions.