It has been revealed that the most likely cause of a fire that gutted the Cutty Sark in May 2007 was an industrial vacuum cleaner that had been left switched on for two days.

The Metropolitan Police announced the findings following a lengthy investigation into the blaze at the attraction, located in Greenwich, London. A failure of the vacuum cleaner's motor is being blamed for the fire, which is said to have started on the lower deck towards the stern of the 280ft (85.3m) ship based on CCTV footage and physical evidence from the site.

Metropolitan Police has ruled out any possibility of arson at the Cutty Sark, the last surviving tea clipper in the world, which was undergoing a £25m conservation project at the time of the blaze. Work to protect it from corrosion and to make it more accessible to visitors was being carried out as part of the project, part funded by an £11.75m grant from the Heritage Lottery Fund in June 2007.