Because at least one of the cars was carrying a toxic, highly corrosive substance, they're being as careful as possible. Crews say they expect to be out there for another 36 to 48 hours. Fortunately, nothing has spilled yet.
Classes at nearby Colton High School and Wilson Elementary School were canceled Tuesday as a precaution.
"Nothing has happened so far, and we want to keep it that way," said Tom De Bellis of the Colton Fire Department. "We don't want guys to get hurt, we don't want the public to be in danger, we don't want to shut the freeway down."
The incident happened just after 2 a.m. A Union Pacific freight train was heading south, navigating through a sharp curve turning west toward the Colton station when, for some reason, six cars derailed. Some of them hit a Burlington North Santa Fe train, which was travelling on a neighboring track in the same direction.
"I'm only two blocks away, but the trains always go through, you can hear the horns, but this one was like a big cha-bang, just out of the norm," said Steven Herrera of Colton.
One tank car was carrying hot asphalt, and two were carrying ferric chloride. Authorities said there were no immediate signs of any leaks.
"Terrible, terrible, this is just not supposed to happen, not in this day and age, you know with modern technology the way it is, I can't believe a freak accident would happen," said Armida Hernandez of Colton.
The accident happened underneath Interstate 10, so authorities closed the roadway between Pepper Avenue and the 215 Freeway for a couple hours as a precaution. It reopened before the busy morning commute.
"They thought it hit the freeway pillar, so they closed the freeway down because they didn't know if it affected it or not," Herrera said.
Metrolink said there were several service interruptions in the area. Trains 803, 805 and 683 were canceled.
The cause of the crash remains under investigation. So far, no injuries have been reported.
"At least, we have God to thank for that, yeah, no one was hurt, that's good," Hernandez said.