A man and two girls were walking to school when the driver of the SUV apparently lost control, jumped the curb, and hit them. The vehicle eventually stopped on an embankment.
A 2-year-old girl is in critical condition, and a 4-year-old girl and an adult suffered moderate injuries. The 2-year-old and the adult were airlifted to L.A. County-USC Hospital. The other child was rushed by ground ambulance to UCI Medical Center.
The names of the victims have not yet been released.
Sheriff's deputies haven't determined why the driver went up on the curb. They say the road was drying from the overnight rain, and the driver was looking for a parking spot to drop off his son at the school.
Witnesses say the man may not have immediately realized just how serious the accident was.
"He got out and opened up the truck of the car and got the backpack," said one witness.
Another witness says the man took his child to school before coming back to see if everyone was OK.
"And then he came and he said 'I'm sorry, I'm sorry, I'm sorry,'" said the witness.
Investigators say the driver of the SUV is taking a voluntary blood alcohol test.
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