Technology company Mindsheet, which has just six staff, has designed a fleet of five-kilo robots which can automatically guide themselves into an urban battlezone to seek out bombs, snipers, and street militias before foot soldiers head in.

The company, based at Langstone Technology Park, Havant, showed off the 'robot spies' in a trial on Thursday, ahead of the Ministry of Defence's Grand Challenge competition in August, when the most innovative new military devices will be pitted against one another.

If Mindsheet's project is successful the firm said it could be looking at lucrative research funding to develop the expendable robots even further. The one-metre vehicles cost around £2,000 apiece, less than a smart mortar, and can travel at 35mph.

'There's a reason for that,' said managing director Raglan Tribe. 'You don't want people to catch them, or they'll end up on eBay.

'I think it's quite a cool concept we've got, and really helps show what the firm can do. There are all kinds of things you can use them for, like mine detection and perimeter patrols. They also have a lot of civilian applications from wandering corridors to possibly even working in rescue situations after an avalanche.

'Electronics are getting cheaper and smaller. It's a big thing for the military because they don't want soldiers to be taken up with piloting vehicles. If they can have devices which will just do what they've been told, it makes things much easier.'

The robots would automatically enter a town along pre-planned routes set by Storm Shadow cruise missile software, and use sensors to avoid obstacles, even climbing steps.

They can also work together, summoning one another if they spy something interesting, and alerting human masters to danger.

The dry run, involving four robots, was at Mr Tribe's home in Rowlands Castle, ahead of the Grand Challenge finals on Salisbury Plain in August.