SAN FRANCISCO (CBS SF) — A “major medical emergency” prompted the closure of BART’s Powell Street station in San Francisco on Wednesday morning for just under 20 minutes, according to the transit agency.

The emergency was reported shortly before 11:20 a.m. Trains are going through the station without stopping, and are single-tracking between the Embarcadero and 24th Street Mission stations, BART officials said.

BART officials said there was a preliminary report of a person on the tracks.

Trains were going through the station without stopping while emergency crews responded, but normal service resumed about 20 minutes later after authorities learned there had been someone in the trackway but they weren’t seriously hurt, BART spokesman Chris Filippi said.

At about 11:38 a.m., BART officials said the situation had been resolved. Riders were advised to expect 15 to 20 minute delays traveling through San Francisco.