Disturbing video shows Sydney schoolboy being kicked and punched on the ground

Disturbing video has emerged of a gang of western Sydney school students circling, punching and kicking a 15-year-old boy on the way home last week.

He spent the night in hospital and now police are trying to track down his attackers.

It was after school at Chester Hill train station that the student was circled.

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Video shows, while he's not watching, a punch signals the rest of the gang to join in.

The boy from Sefton High runs for his life.

"I tried to escape by running to the park next to the station and I lost my balance and fell on the ground," he said.

What happens next defies belief.

The young thugs unload on their helpless victim, filming the act themselves before the cameraman even joins in.

"I just fell to the ground and they kept hitting me and kicking my body," he said.

"They were around, more than 10 people."

The young boy doesn't want to be identified as he's fearful they'll do it again.

But after the injuries he suffered on Wednesday afternoon he spent the night in hospital.

The boy's father distraught father just hopes his son's attackers are caught and that no other family has to go through a similar story.

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"Make sure this never happen again in the future at any school in this area or even in Sydney," his father said.

And while the physical injuries are healing there's no timeline on when he'll recover mentally.

He's too afraid to return to school and won't even visit the local shops to get a bottle of milk.

"I don't dare to watch the video I'm mentally traumatised," the victim said.

That video is central to the police investigation.