What to Know A Long Island mother found her 11-year-old daughter unresponsive in the family SUV after running errands Tuesday

The girl's lips were blue, and the car had been sweltering with the windows up, police say. EMS efforted CPR; the girl died at the hospital

It's not clear how long the girl had been inside the car before the mother realized she was missing inside the house

An 11-year-old girl has died after she was found unresponsive inside a sweltering car at a Long Island home Tuesday afternoon, Suffolk County police say.

The girl's mother called 911 just before 4 p.m. to report finding her daughter unconscious in the car in their driveway in Coram, and that the girl's lips were turning blue, according to Suffolk Police Det. Lt. Kevin Beyrer. The mother brought her child into the house on Kathleen Crescent and tried to give her CPR until paramedics arrived.

EMS continued CPR efforts while taking the girl to Stony Brook University Hospital, but she was pronounced dead at the hospital.

"This is an unspeakable tragedy," said Beyrer.

Police would not say how long the girl was left in the car.

It appears the mother, the girl and two other children were out running errands in their car, and when they returned, went back into the house, assuming the girl was with them, Beyrer said.

At some point, the mother realized the 11-year-old girl was not with them in the house and went back out to the car, and found her daughter in the backseat.

The car was "relatively new" to the family, but the family had been in and out of the vehicle many times, police said.

"She was a sweet little girl," neighbor Sott Krusen said. "Our kids played together. She was very loving. She's just a wonderful kid."

"I can't imagine what the family is going through right now," he said. "It's just a horrible thing."

The temperature in Coram reached a high of 91 degrees Tuesday but the CDC says temperatures inside a car can rise almost 20 degrees within the first 10 minutes, even if the window is cracked open -- almost certainly making the temperature inside the car well into the triple digits.

According to advocacy group Kids and Cars, an average of 37 children have died in the U.S. each year since 2013 from being trapped inside hot cars; 88 percent of them are age 3 and younger.