The driver of a car which struck and killed a toddler in a driveway in Sydney's southwest was "hysterical" after the collision.
NSW Police say the two-year-old girl was struck by the reversing vehicle near a mechanics workshop on Beamish Street at Campsie about 10.45am on Thursday.
The vehicle which hit the girl is understood to belong to the victim's mother.
Superintendent Adam Whyte says police and paramedics responded quickly and administered first aid.
"The driver was absolutely hysterical, as you would imagine," he told reporters in Sydney.
"This is a horrific scene for not only the driver but all those involved, particularly for the police and emergency services."
The critically-injured toddler was taken to the Sydney Children's Hospital at Randwick where she was pronounced dead.
The driver, a 43-year-old woman, has also been taken to hospital for mandatory blood and urine testing.
"The death of a child is always very, very traumatic," Supt Whyte said.
"For the emergency services, it's one of those jobs that nobody ever wants to go to."
Local man Freddy Farhat said the young girl's uncles, who run a nearby business, were quickly on the scene performing CPR.
"I'm just shocked to see something like that," Mr Farhat told Network Ten.
"I just heard the frantic screaming from the siblings."
Support services have been offered to the officers who were first on the scene.
Crash investigators spent Thursday afternoon speaking with witnesses and combing the site for evidence.
Supt Whyte pleaded with motorists to approach the busy holiday season with caution.
"It is a timely reminder to all drivers, particularly when you're reversing, to be aware of your surroundings," he said.
