The woman was walking with her dog just north of the Hayward Station when she was struck at about 2:15 p.m. by train No. 535 that was headed for San Jose, said Vernae Graham, a spokeswoman for Amtrak, which also runs Capitol Corridor.
Graham said preliminary reports indicated the dog also died.
Around 10:50 a.m., a person intentionally jumped in front of southbound Amtrak train No. 711 near the Grayson Street crossing in Berkeley, according to Graham.
She said 20 passengers were on the Hayward train and 26 were on the Berkeley train, but no further injuries were reported in either crash.
As a result of the Hayward crash, Capitol Corridor train No. 538 headed from San Jose to Sacramento was canceled and passengers were deferred to train No. 540 that was scheduled to leave 45 minutes later, she said.