A 15-year-old boy has died and a 14-year-old boy has suffered a severed arm following a horror jetski accident.

Emergency services were called to the Georges River at Tom Uglys Bridge, Sylvania, in Sydney’s south, about 6pm on Tuesday following reports of people in the water after a possible jetski crash.

Police and paramedics reportedly jumped into the water upon locating the two teens.

The 15-year-old was found dead in the water while the 14-year-old was sedated and placed in an induced coma before being taken to Sydney Children’s Hospital in a critical condition.

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Investigations are continuing.