BART officials closed three East Bay stations on Sunday afternoon and told riders who take the Fremont lines to expect 15-minute delays during this morning's commute, and probably for the rest of the week.

The closures and anticipated delays were caused by a series of electrical fires Saturday at the South Hayward train yard. The fires damaged cables leading from a tower that helps control the trains, which will have to be operated manually on tracks south of the Bay Fair Station until repairs are complete, said BART spokesman Jim Allison.

"There was physical damage to a very critical component of the train control system," Allison said. "The tower at the Hayward yard, where we move trains around and get them ready to go, is out of commission."

Service was halted between the Hayward and Fremont stations for about 16 hours on Saturday. Trains were running at all stations Sunday morning, but BART officials closed the South Hayward, Union City and Fremont stations again at 2 p.m.

Trains had to be transferred from the South Hayward yard to various stations throughout the system to prepare for the weekday commute, and with automated systems not working, the transfer process was taking too long, Allison said.

Buses were running between the main Hayward Station and the three closed stations.

The stations will be open again today, but the same failure in the automated systems will cause 15-minute delays on Fremont trains Monday and for the rest of the week, Allison said.