Emergency services were alerted to the incident late Monday night.

A man has drowned after falling into the water at Sydney Harbour.

Police said the man, who was a wheelchair user, had fallen into the harbour at Towns Place Wharf, Millers Point.

Emergency services were called about 10.45pm on Monday, with police jumping into the water to rescue the man.

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He was pulled to shore and officers performed CPR until paramedics arrived.

Despite their best attempts the man could not be saved and was declared dead at the scene.

He is yet to be formally identified.

“A crime scene has been established, and officers have commenced an investigation into the incident,” police said.

“A report will be prepared for the information of the Coroner.”