One teen dead and another in hospital after Sydney jet-ski crash

A jet-ski crash in Sydney's south has claimed a teenage boy's life and left his friend with a severed arm.

Emergency services were called to the Georges River about 6pm yesterday after two girls on the shoreline saw pieces of the watercraft floating in the water and then spotted a 14-year-old boy yelling out for help and going in and out of consciousness.

It's believed the boy and his 15-year-old friend, who was found dead nearby, hit an obstacle and were thrown into the water at Tom Uglys Bridge in Sylvania.

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One of the first responding police officers dived into the water to pull the surviving boy to the edge before he was rushed to Sydney Children's Hospital for treatment on what police described as a severed arm.

Inspector Timothy Carter described the officer's actions as "heroic".

"The police have done their best to try and save these kids' lives," he said.

"And it's, you know, we obviously feel great empathy towards the families."

Family friend Fred Nagi sent his condolences to the family of the boy who died.

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The 14-year-old's distraught father told 9news he believed the young boys were on their way home when the accident happened and might have hit a barge.

It was already dark at the time.

A crime scene has been established as police investigate and prepare a report for the coroner.

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