A computer failure interrupted BART commuters during their their travel Thursday morning as the transit agency lost service through the Transbay Tube and most of downtown San Francisco and on its Green and Red lines.

BART spokesperson Michelle Robertson said the agency repaired the problem by 9:15 a.m. but that major delays were expected in the aftermath.

It all started about 8:20 a.m. when BART first announced the initial closure. They announced about 8:32 a.m. that they’d lost the Green Line service from the Berryessa North San Jose station to the Daly City station. A minute later they said the Red Line from Richmond to Millbrae also was down.

Robertson said the problem had to do with the failure of computer network hardware but that personnel repaired the problem.

The Orange Line from Richmond to Berryessa/North San Jose; the Yellow Line from Antioch to the San Francisco Airport, and the Blue Line from Dublin-Pleasanton to Daly City remained open but not through the Transbay Tube or downtown San Francisco.

During the delay, San Francisco-bound riders from the East Bay were urged to use those three lines. South of San Francisco, shuttle trains were available between the San Francisco Airport and Millbrae station and those riders could then transfer to the Yellow Line.

Muni also honored BART tickets in San Francisco between the Embarcadero station and the Balboa Park station.

Please check back for updates.