BART train service is being affected Thursday morning by someone who barricaded themselves in a building at the agency's Hayward Maintenance Complex.
BART spokesperson Chris Filippi said as of about 6:40 a.m. that someone he described as an "unstable individual" trespassed into the maintenance facility and barricaded themselves while allegedly being armed with a knife.
The maintenance yard has been safely evacuated with no injuries reported, and BART police are working to resolve the situation, Filippi said.
He said there is limited Green Line service between Berryessa and Daly City since trains can't be dispatched from the Hayward facility, but all stations are open during the police activity.