Jenna Betti was killed in Martinez Sunday evening by a Burlington Northern Santa Fe train when she went back on the tracks to retrieve a cellphone that she had dropped, investigators said.
According to a message from Betti's mother, which was posted on social media sites, the 14-year-old was with her boyfriend on the tracks just before she was hit.
BNSF Railway spokeswoman Lena Kent said three crewmembers aboard the train noticed the two pedestrians on the tracks. They said the two initially got off, but then the girl went back to get something.
Kent said the train was heading from Richmond to Fresno at the time of the incident.
Betti was a popular eighth-grader at Martinez Junior High School, where she played on the soccer team and was involved in many school activities.
KGO-TV and the Associated Press contributed to this report.