A suspicious device later determined to be harmless was found on a commuter train at the San Francisco Caltrain Station delaying late night service, officials said.

Transit officials said that at about 11:20 p.m. Wednesday a suspicious package was discovered on northbound train #197 at the station. The train had just arrived in San Francisco from its run northward from San Jose.

At the time of the discovery, the train had emptied of passengers.

The San Francisco Police Department’s bomb squad was called to investigate the package, officials said, and the station was closed during the investigation and no trains were allowed to leave the station.

Transit officials said the investigation was completed about 1:30 a.m. and the package was determined to be harmless.

Northbound train #199, which left the San Jose Diridon Station at 10:30 p.m., was due to arrive in San Francisco at 12:01 a.m. This train was terminated Caltrain’s 22nd Street Station. Southbound train #198 was scheduled to depart San Francisco at 12:01 a.m. This train did not depart.

Transit officials said the 64 passengers at the San Francisco station waiting for the last southbound train of the evening, train #198, were taken by Muni bus to Caltrain 22nd Street Station, where they were able to board a southbound train.

There were no other train delays. Caltrain’s regularly scheduled service was operating on its normal schedule Thursday morning.