A five-month-old girl has died and a five-year-old child is in a serious condition after being struck by a car in a carpark in Sydney’s south-west.

Emergency services were called to Brookfield Road, Minto about 3.30pm after reports that a pedestrian had been struck by a car.

When police arrived, they found the two children in a serious condition after being hit by an SUV.

Police attempted CPR on the infant before she was treated by paramedics, but she died on the scene.

The five-year-old was taken to The Children’s Hospital at Westmead in a serious but stable condition.

“There were a few people traumatised by seeing it,” said a witness.

The 35-year-old behind the wheel was uninjured.

Crash investigators have speculated that the driver may have accidentally put the car in reverse instead of forward.