The Los Angeles-bound train on the Antelope Valley line struck a vehicle on the tracks west of the Burbank station at 3:15 p.m., Metrolink said, and announced delays of numerous other trains via Twitter.
An elderly man, the only person in the car, was taken to a hospital in critical condition, a Burbank Fire Department spokesman said.
The train had 130 passengers, and there were preliminary reports of three minor injuries, Metrolink spokesman Jeff Lustgarten said.
"Traffic's going to be delayed for hours," a spokesman for the Burbank Police Department said.
Levon Gharibian, 24, said he was driving at that intersection at the time of the crash. "Had my windows closed, but heard a thump that would resemble the sound of driving over a manhole," he said in an email. "Car looked mauled up."
"A lot of times people don't realize how quickly that train is coming," Lustgarten said. "Our hearts go out to the individual and the family."
In a sad coincidence, he said, September is national rail safety month. Metrolink is planning an event Thursday at the Orange station to raise awareness about the importance of exercising caution on and around the tracks, he said.
Trains can't steer out of the way of trouble, he noted, and they take a quarter-mile to half a mile to stop.
In 2009, a Los Angeles Times article called the rail crossing at San Fernando and Buena Vista one of Metrolink's most dangerous. "The intersection is a maze of sharp turns and confusing signals that require drivers to move with split-second timing," the article said.
Lustgarten said he was not aware of any safety improvements at the crossing since then but has not been working at Metrolink the whole time. The crossing arms were down at the time of Tuesday's crash, he said.