The vehicle was struck in the area of East Hunter Avenue and South Grand around 5:30 p.m. One person inside the vehicle was killed.
No passengers on the train were injured.
A dog that was inside the vehicle survived the crash and was rescued by authorities. An image provided by Santa Ana police showed the canine with some bruising and blood on a leg but otherwise appearing uninjured.
The Metrolink OC Line 689 train was heading to downtown LA's Union Station.
The train was stopped on the tracks while investigators looked into the cause of the collision.
The incident was causing delays to seven trains on two lines. Updates on train delays are posted on Metrolink's Twitter page.