A 36-year-old man, who had been disqualified from driving, has been charged after a young boy was killed when a car ploughed into him as he was walking to school.

Ryan Wang, 12, was walking to Sydney Technical High School in Hurstville, where he was a student, with a friend when he was struck on Forest Rd about 8.40am on Friday.

Watch the video above

Police said the boy was trapped under the car for a short time before he was released.

He was treated at the scene by paramedics before being taken to Sydney Children's Hosptial at Randwick in a critical condition.

Tragic circumstances

He was pronounced dead on arrival at the hospital.

St George Acting Superintendent Craig James said it was a tragic set of circumstances.

Police at the scene of a fatal accident on Forest Road in Hurtsville. Credit: 7NEWS

"This was at 8.40am, school drop off, so there were a number of students being dropped off to school by their mums and dad, there were teachers who ran out ... this is absolutely awful," James said.

"I can confirm he was a Sydney Tech High School student, he was walking to school this morning at 8.40am," James told reporters.

Chevron Right Icon 'This was at 8.40am ... so there were a number of students being dropped off to school.'

It's alleged the driver, Rabih Abdul Rahman, ran a red light before hitting the 12-year-old, who was crossing the road.

Vision from the scene shows the car mounted the footpath and crashed through the school fence.

More on 7NEWS.com.au:

"This is a tragic, tragic set of circumstances ... so any further information that we can get that can assist with our inquries please contact Crimestoppers," James said.

Desperate efforts

It's understood many members of the school community witnessed the accident.

The education department is working to provide urgent counselling support to those impacted, including the boy's family.

NSW Ambulance Inspector David Stride says bystanders, including an off-duty nurse, desperately tried to resuscitate the boy while waiting for ambulance crews to arrive.

The 12-year-old student was just metres from Sydney Technical High School in Hurstville. Credit: 7NEWS

Five ambulance crews and a medical team were sent to the scene but desperate efforts to save the boy were unsuccessful, said Stride.

"Unfortunately the child was unable to be revived," Inspector Stride said.

He said it was a "very distressing" for everyone involved.

"There were a lot of people upset, a lot of people who witnessed the accident."

The 36-year-old man was taken to hospital for mandatory testing and has been charged with manslaughter, dangerous driving occasioning death, driving whilst disqualified and other traffic offences.

He was refused bail and appear in court on Saturday.