OAKLEY -- Authorities said a person was killed Wednesday afternoon when they were struck by an Amtrak train as they stood on the tracks near the city's downtown area.

The incident took place around 3:35 p.m., Amtrak spokeswoman Vernae Graham said, when a westbound San Joaquin 713 train struck the person. The person's name, age, and gender were not available.

Contra Costa Sheriff's deputies were investigating at the scene of the incident, near Main Street and Vintage Parkway. The person was not at a train crossing when they were struck, Graham said.

There were no reports of injuries aboard the train. The maximum speed for trains in that area is 79 mph.

Train service was expected to be delayed while authorities investigated the scene.

David DeBolt covers breaking news. Contact him in Richmond at 510-262-2728. Follow him at Twitter.com/daviddebolt.