California Highway Patrol officials responded to the crash, involving two FedEx semi-trucks and a car, shortly before 1:30 a.m. near the Lake Avenue exit.
Officials said the car struck a big rig and the driver took off. Soon after, a second semi-truck also crashed at the scene, causing the first FedEx truck to overturn on its side at the center divider and onto Metro train tracks.
CHP investigators said skid marks at the scene showed that the second big rig attempted to brake before crashing into the initial wreck.
"For a tractor-trailer, especially when they're loaded, the braking distance is going to take a lot longer than a vehicle," explained CHP Officer Kevin Tao.
Watch this FedEx big rig get uprighted after a nasty crash on the 210 freeway in Pasadena that left a trailer blocking both directions of @metrolosangeles’s Gold Line. Live updates throughout the morning on @ABC7. pic.twitter.com/WpT5x3CLJH— Chelsea Edwards (@abc7chelsea) April 26, 2018
Metro shut down both directions of the Gold Line near Lake Station, and officials said the closure may last for days. Meantime, buses replaced trains between Memorial Park and Allen Station.
All lanes of the 210 Freeway have since reopened.
GOLD LINE: buses replace trains between Memorial Park-Allen due to freeway collision blocking tracks. Allow extra travel time or consider alt route options: https://t.co/BDhhDQIMvO pic.twitter.com/jEEnBbLOol— Metro Rider Alerts (@metrolaalerts) April 26, 2018
The driver of the second big rig was transported to a local hospital with minor injuries. The other FedEx driver was not hurt, officials said.
The person behind the wheel of the car in the initial crash is outstanding, and the cause of the collision was under investigation.