The Labour Department says it's launched an investigation after an air conditioning technician plunged to his death while working at an industrial building in Tsuen Wan on Saturday.

Police say they were called at about noon to reports that the worker slipped and fell from external scaffolding at the Wah Chun Industrial Centre on Chai Wan Kok Street.

Officers said he fell from above the tenth floor of the building.

The man was confirmed dead at the scene.

The Labour Department said it immediately deployed staff to the scene, and is looking into the cause of the accident.