A group of computer hackers has claimed to have broken into a US computer which controls military satellites. The group, calling itself MOD, or Masters of Downloading, contacted a security Website last week with evidence of the breach - secret files taken from the Defense Information Systems Network - the owner of the site, John Vranesevich, said.

The group claimed, in online interviews, to have stolen software which controls military communications and Global Positioning Systems (GPS) satellites. A defence department spokesman said military officials were "aware of the intrusion and looking into the matter". The MOD hacking follows a string of cyber assaults on US military computers last February, which were traced to two Californian teenagers and their 18-year-old online teacher, an Israeli hacker called "Analyzer".