The US Army will be going into battle with armed robots from next year.

The Talon series machines are currently used for reconnaissance in dangerous areas, but are due to be fitted with M240 or M249 machine guns or Barrett 50-calibre rifles. The army is also testing versions armed with rocket and grenade launchers.

The robots, built by American manufacturer Foster-Miller, have a range of about 20 miles and can move at up to four miles an hour. They are not independent, but are wirelessly controlled by human operators.

The devices were first used in Afghanistan and have been tested in Kuwait and Iraq since last year.

Robots independent of human control are of great interest to the Army but, if the results of this year's Defense Advanced Research Projects Agency Grand Challenge are anything to go by, they will be a long time coming into service.

The contest, with a £1m prize, called for an autonomous vehicle to complete a 150-mile trip, but no contender managed more than seven miles before crashing.