Police arrested a 22-year-old man on suspicion of driving under the influence of drugs after the truck crashed into a popular area of Fullerton filled with people leaving bars and restaurants shortly before closing time.
"It was a very chaotic scene," police Lt. Jon Radus said.
The Toyota Tacoma jumped the curb, struck people and then crashed into a tree, Radus said. Some of the victims were trapped under the truck.
"One of the girls was screaming, 'Help, help!'" bystander Sohrab Gill said. "I saw some blood coming out of her nose."
Injuries ranged from moderate to critical and the victims are between 18 and 49 years old, the Orange County Register reported.
Christopher Solis of Anaheim was arrested on suspicion of felony DUI causing great bodily injury. It wasn't known if he has an attorney.
This story has been clarified to show police believe the suspect was under the influence of drugs, not alcohol.
Information from: The Orange County Register, http://www.ocregister.com
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