Monday's Caltrain fatality was identified today (Tuesday) as Heather Russell, 29, of Palo Alto.
The Santa Clara County Coroner's Office declined to state whether her 11:30 a.m. death was a suicide.
Russell reportedly sat down between the Caltrain tracks north of the San Antonio station and was killed late Monday morning by a southbound train, according to a police detective.
Russell entered the southbound tracks behind an apartment complex on Del Medio Avenue, at the Mountain View/Palo Alto border, at approximately 11:25 to 11:30 a.m., according to officials.
The area, which is surrounded by shrubbery and not easily seen, is one of the few access points not barricaded by a tall chain-link fence, according to Detective Victor Lopez of the San Mateo County Sheriff's Office Transit Police Bureau.
"She sat down between the gauge of the tracks. The engineer went into emergency braking and honked the horn, then the train struck her," Lopez said.
Caltrain service was delayed approximately 20 minutes in both directions and trains were routed to a single track.
The train engineer, who was not identified, was returning to San Jose and was pulled from duty as a matter of Caltrain policy. The engineer's state of mind is about what one would expect after being involved in a fatality, Lopez said.
"It's a horrible incident," he said.