US appoints first cyber warfare general

The newly promoted four-star general, Keith Alexander, takes charge of the Pentagon's ambitious and controversial new Cyber Command, designed to conduct virtual combat across the world's computer networks. He was appointed on Friday afternoon in a low-key ceremony at Fort Meade, in Maryland.

The creation of America's most senior cyber warrior comes just days after the US air force disclosed that some 30,000 of its troops had been re-assigned from technical support "to the frontlines of cyber warfare".

The creation of Cyber Command is in response to increasing anxiety over the vulnerability of the US's military and other networks to a cyber attack.

James Miller, the deputy under-secretary of defence for policy, has hinted that the US might consider a conventional military response to certain kinds of online attack.