No trains were going in or out of BART's SFO Station for about an hour Wednesday morning due to an unspecified "police matter" that has yet to be made public.

Train service to the airport was disrupted between 9 a.m. and 10 a.m. this morning, per KPIX, and it remains unclear what the cause of the station closure may have been. Airtrain service through the airport was also reportedly suspended.

Airport spokesperson Doug Yakel tells the Chronicle that police were "clearing an alarm inside the BART station."

BART spokesperson Jim Allison explained in a recorded message for the media tha the police matter began around 8:45 a.m., and train service is now back to normal.

More on this story as we learn more.

Photo courtesy of BART.gov