18-month-old baby girl survives a car crash in a freezing river and is found alive after 14 hours

An 18-month-old girl survived a car crash in a freezing US state of Utah river after being strapped in a car seat upside-down for some 14 hours before being found by a fisherman.

The condition of Lily Groesbeck was stable but critical, according to Salt Lake City hospital.

Her 25-year-old mother, Lynn Groesbeck of Springville, was found dead in the car.

Investigators believed the wreck occurred at about 10.30pm on Friday when a resident near the accident scene reported hearing a noise.

The car struck a cement barrier on the bridge and careered into the river.

It landed under the bridge and was difficult to see from the road.

Police are unsure why the car left the road, and the Utah Highway Patrol is assisting in the accident investigation.

The outside temperature was around 0C while the girl was trapped in the car.

Police said they wouldn't release further details on Sunday unless the girl's condition changed.