A 28-tonne armoured vehicle rolled backwards down a grassy bank on Portland and destroyed a garage, leaving a Southwell family thanking their lucky stars for such a narrow escape.

The prototype vehicle - which hit the headlines during Prince Andrew's recent visit to Weymouth - was being unloaded from a trailer in Southwell Business Park yesterday at about 6.30pm. It sent a shower of bricks over nearby parked cars and stopped just inches on the other side of the wall from there the Nethercott family were about to sit down to their dinner.

According to Dorset Police, a "malfunction" caused the vehicle to roll away and finally come to a stop in the garden of their home in Reap Lane. The ITN website said the manufacturers of the £1 million vehicle did not think it appropriate to comment at this stage, as this is now a police matter.

Nobody was hurt, but fences and cars were damaged. The vehicle was designed to withstand Taliban bomb blasts and has been touted to the British Army as an armoured vehicle suitable for British troops. Prince Andrew recently got into hot water when he visited the Universal Engineering factory on the Granby Industrial Estate and criticised the Ministry of Defence for dragging their feet over a decision to test the Ranger vehicle. He said they should get off their backsides - prompting criticism from those who believe the Royal Family should not enter into political debate.