Police say a 1-year-old girl was left in sweltering car for more than three hours before her death. WVTM's Kalisha Whitman reports.

A 1-year-old girl died Thursday after she was left for hours in a parked car on a sweltering day in Homewood, Ala., NBC station WVTM reported.

Police said they received a call around 1:30 p.m. about a baby locked inside a vehicle. The temperature outside at the time was about 91 degrees, and the temperature inside vehicles can reach life-threatening levels quickly.

The girl was taken to the hospital, where she was pronounced dead.

Chris Conn told WVTM that he saw the mother panicking, ran over and performed CPR on the child, but it was too late. He said the child had been left in the car around 10 a.m.

So far this year there have been at least 21 deaths of children unattended in vehicles, according to a study from the Department of Geosciences at San Francisco State University. In 2012, that number was 33.

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