SAN MATEO (CBS SF) — An adult male was fatally struck by a Caltrain on the tracks at Hillsdale Station in San Mateo, the San Mateo County Transit District said on Wednesday.

The incident happened around 4:22 p.m. and involved train SB #602, the Giants postgame train. There were around 300 passengers onboard the train, none of whom had any reported injuries, officials said.

All trains were stopped in the area for around an hour. Emergency personnel were on the scene investigating the incident.

Caltrain tweeted out a list of delays.

Transit officials said the northbound track reopened with a 20 mph speed restriction through the incident area at 5:31 p.m. At 6:00 p.m., Caltrain said the incident train, SB #602, was released for movement and to make stops at Belmont station before being terminated at Redwood City station.

Both the northbound and southbound tracks were cleared for maximum authorized speed by 8:40 p.m.

The San Mateo County Sheriff’s Transit Police Bureau the county’s Coroner’s Office are investigating the incident.

In an email on Wednesday evening, Alex Eisenhart of the county’s Transit District said, “While it is early in the investigation, this incident appears to have been an intentional act. However, the final cause of death and identification of the individual will be determined by the San Mateo County Coroner’s Office.”

“No matter what the circumstances, it is always regrettable when a life is lost. Caltrain reminds everyone to be safe around train tracks. Caltrain also would like to thank our passengers for their patience as we deal with these sad situations,” Eisenhart continued.

This incident is Caltrain’s fourth fatality of 2019.