Computer spies have hacked into the Pentagon's most costly weapons program, a US newspaper reported Tuesday, raising the prospect of adversaries gaining access to top-secret security data.
Citing current and former government officials, The Wall Street Journal said cyber-intruders were able to copy several terabytes of data on the 300-billion-dollar Joint Strike Fighter project, which may make it easier to defend against the aircraft, also known as the F-35 Lightning II.
A terabyte is 1,000 gigabytes.
The officials said similar breaches were recorded at the US Air Force's air traffic-control system in recent months, while the Journal had also earlier reported that spies hacked into computers used to manage the US electrical distribution system and other infrastructure.
The latest attacks signal an escalation in attempts by intruders to gain access to vital US security data over the past six months -- or at least US awareness of such attacks, a former official said.
"There's never been anything like it," the former official was quoted as saying, adding that other military agencies as well as private contracting companies have been affected.
"It's everything that keeps this country going," he added.
It was not immediately clear how severe the breach was, or exactly who the hackers were, but the most sensitive data on the fighter project is reportedly kept on secure computers not connected to the Internet.
The newspaper cited unnamed former US officials saying the attack appeared to have originated in China.
A recent Pentagon report stated that China's military had made "steady progress" in developing techniques for improved online warfare, as part of an effort to compensate for an underdeveloped military, the Journal said.
Earlier this month China denied the Journal's report that Chinese and Russian hackers had attempted to plant viruses in the US power grid.
(c) 2009 AFP