UNION CITY — An equipment problem on its tracks caused BART to shut down service between its Union City and Bay Fair stations early Wednesday, officials said. The closure affected trains on BART’s green line between the Berryessa and Daly City stations.

BART service resumed Wednesday morning between Bay Fair and Union City stations after an earlier equipment problem on the track halted trains, the Bay Area Rapid Transit District said. Commuters were advised to seek alternative forms of transportation during the service stoppage announced at 6:49 a.