HAYWARD — Adding to the already ugly traffic situation, the South Hayward BART station was closed for at least four hours Wednesday night after an explosion in an underground electrical vault killed the power there. Trains did not lose power and were running through the station, but they did not stop.

At 10 p.m. Wednesday, BART officials said they expected the station to stay closed until at least midnight.

BART set up buses to shuttle passengers between the South Hayward and downtown Hayward stations.

The explosion was reported to the Hayward Fire Department shortly before 6:30 p.m. Power also was out in nearby neighborhoods for a short time.

BART spokesman Jim Allison said the darkened station was closed at 6:40 p.m. The Fremont-Richmond line remained in service at all other stops.

PG&E spokesman J.D. Guidi said 7,095 customers in Union City and Hayward lost power from 7:10 to 7:41 p.m. Those north of Decoto Road along Mission Boulevard and east of the BART tracks to Tennyson Road were without power during that time.

Guidi said power was restored everywhere except for the South Hayward BART station.

For updated information, call the BART hot line at 510-874-7464.

— Eric Kurhi