BART service has been halted between South Hayward and the Berryessa station in San Jose during the Friday morning commute, officials said.
Around 5:20 a.m., the agency issued a service advisory about the issue, which they said involved an equipment problem. In a subsequent update, BART said wayside equipment was damaged due to suspected vandalism.
As of about 6:30 a.m., BART said crews were working on repairs, but there is no estimated time on when service would resume through the area.
Other parts of the system in the East Bay, San Francisco and Peninsula are not affected. Green Line trains from Daly City are going as far as the Bayfair station in San Leandro, while Orange Line trains from Richmond are going as far as Hayward.
The agency has sent extra staff to help at stations with no train service. AC Transit is providing free mutual bus service connecting impacted stations between Hayward and Milpitas.
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