The documents leaked by NSA whistleblower Edward Snowden, apart from the multi-million 'black budget' of the US intelligence agencies, also revealed that the department executed 231 offensive cyber operations in 2011.
The offensive cyber operations are expected to cost 278 million dollars in the current fiscal year.
According to the Washington times, under an extensive effort code-named GENIE, the US intelligence agents break into foreign networks so that they can be put under surreptitious US control.
The 652 million dollar GENIE project has placed 'covert implants', which are sophisticated malware transmitted from far away, in computers, routers and firewalls on tens of thousands of machines every year and NSA plans to expand those numbers into the millions.
The report said that of the 231 offensive operations conducted in 2011, nearly three-quarters were against top-priority targets which include adversaries like Iran, Russia, China and North Korea and activities such as nuclear proliferation.
Former officials associated with the NSA said that if one is neutralizing someone's nuclear command and control, that's a huge attack adding that the greater the physical effect, the less likely it is that an intrusion can remain hidden.