The station closed about 9:30 a.m. because of the unidentified item, causing delays in both directions across the BART system as trains were been unable to run through Civic Center, officials said. BART announced about 10:30 a.m. the station has restored service.
BART police officers had cleared the area on Market Street between Seventh and Eighth streets of pedestrians with assistance from San Francisco Police Department.
The investigation also shut down Muni light rail service at Civic Center.
Officials said riders should expect residual delays from the incident to continue across the transit system.
Jenna Lyons is a San Francisco Chronicle staff writer. Email: email@example.com Twitter: @JennaJourno