Three workers hurt in NSW crane collapse

Three men have been injured when a crane collapsed at a building in North Sydney.

The three workers - aged 24, 28 and 36 - were inside the crane when it malfunctioned, collapsed and hit a concrete well about 11.30am on Sunday, police said.

The three were attached by lanyard, suspended about 60 metres off the ground, when the crane fell, but the 24-year-old managed to extricate himself and climbed to safety on the roof of the Meriton building.

Fellow workers used a second crane to lower a metal box to the trapped men, lowering them to the ground.

All three were taken to Royal North Shore Hospital with non life-threatening injuries.

Engineers will assess the site and SafeWork NSW will investigate the incident.