A Sydney man has died of critical injuries after he fell from an eight-story balcony in the eastern suburbs.

Police had been attempting to speak with the 40-year-old man, and were waiting at the front door of his unit block on Onslow Ave in Elizabeth Bay, when someone phoned Triple-0 to report a fall.

The balcony and the man were not in view of the officers, who later confirmed the injured man was the person they had been urging to come to the front door, police said.

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They provided assistance until NSW Ambulance paramedics arrives, but the man died of his injuries.

Why the man was on the balcony, and how he came to plunge to his death remains unclear at this stage.

A critical incident has now been launched to investigate the matter.

Police had been seeking the man out as part of ongoing investigations, but had instead spoken with a 38-year-old woman inside the unit shortly before the man’s fall.

The woman had refused police entry to the unit, NSW Police allege.

The woman left the unit block a short time after speaking with police, and officers waited outside the building until they received reports of the fall.

A crime scene has now been established and a critical incident team from Inner West Police Area Command will investigate the circumstances surrounding this incident. The investigation will be subject of an independent review by the Professional Standards Command and oversight by the Law Enforcement Conduct Commission.