Screws that broke and allowed a surgical light to come crashing down in a Hong Kong operating theatre showed signs of metal fatigue that would have been identified if checks had been carried out properly, the Hospital Authority has said.

Announcing its findings into the incident at United Christian Hospital last weekend, the authority on Friday said it was “extremely dissatisfied” with the work of contractor Getinge that was responsible for the lights. It reserved the right to take legal action and would pass the case to law enforcement if necessary, the organisation warned.

Dr Eric Lim Chaw-hyon, a materials testing expert who led the investigation, said all six screws used to secure the light to a fixture attached to the ceiling of the operating room were broken, with at least four of them showing signs of metal fatigue.