Four people are dead after a two-car crash in Thornton on Saturday started their car on fire, police said. Thornton officers were investigating the fatal two-car crash near the intersection of Thornton Parkway and Washington Street around 8 p.m. Saturday, according to a statement on social media from the police department. The intersection is east of Thornton City Hall and north of the Pinnacle shopping mall. Police said one of the cars caught fire after being hit in the crash, killing all four people inside.