The San Mateo County Coroner’s Office has identified a man killed on the Caltrain tracks in San Mateo on Wednesday afternoon.

Christopher Hall, a 41-year-old San Bruno resident, was struck and killed by a northbound train near First Avenue at about 3:15 p.m., Caltrain spokeswoman Christine Dunn said.

Investigators have not determined why Hall was on the tracks.

Hall was the 11th person killed on the Caltrain tracks this year, Dunn said. Nineteen people died on the tracks in 2009.

Wednesday’s incident caused system-wide delays of up to 30 minutes as trains were forced to single-track through the area until about 5 p.m.