A 5-year-old girl and a 4-year-old boy were among four people injured Monday morning near downtown Modesto when two cars collided at Sixth and I streets, police reported.
The investigation is ongoing, but police spokesman Sgt. Craig Gundlach said it appeared that one driver ran a red light and hit the other car.
The girl was taken by helicopter to the University of California Medical Center in Sacramento to be treated for serious injuries, police said. She was in critical condition Monday night after surgery.
The boy was taken to a local hospital with minor injuries, Gundlach said. Neither child was restrained by a safety seat. Their names were not released.
The driver, Beatriz Jimenez, 20, and her passenger, Juana Jimenez, 32, also were hurt, Gundlach said, but their injuries were not life-threatening. Juana Jimenez is the mother of the children; Beatriz Jimenez is their aunt. All are from Modesto.
Police are trying to determine whether Rupindar Tamana, 23, of Turlock ran a red light in her silver, compact Mercedes sport utility vehicle while heading north on Sixth Street at about 8:50 a.m. Jimenez's black, four-door Toyota sedan was heading east on I Street when the crash occurred.
Gundlach said the crash did not appear to involve drugs or alcohol.