U.S. intelligence services conducted 231 offensive cyber-operations in 2011, with nearly three-quarters carried out against top-priority targets, including China and other U.S. adversaries.

The disclosure, revealed in top-secret documents provided by NSA leaker Edward Snowden to The Washington Post, provides new evidence that the Obama administration's growing ranks of cyberwarriors infiltrate and disrupt foreign computer networks.

Three quarters of the?231 offensive operations conducted in 2011 were against top-priority targets, which former officials say include adversaries such as Iran, Russia, China and North Korea and activities such as nuclear proliferation. But the document provided few other details about the operations.

Additionally, under an extensive effort code-named GENIE, U.S. computer specialists break into foreign networks so that they can be put under surreptitious U.S. control, according to the Washington Post report.?

Budget documents?reveal the US$652 million project has placed "covert implants," sophisticated malware transmitted from far away, in computers, routers and firewalls on tens of thousands of machines every year, with plans to expand those numbers into the millions.

The documents provided by Snowden and interviews with former U.S. officials describe a campaign of computer intrusions that is far broader and more aggressive than previously understood. The Obama administration treats all such cyber-operations as clandestine and declines to acknowledge them.

In?a separated report, Guardian reporter Glenn Greenwald, who obtained secret documents from Snowden, said Mexican President Enrique Pena Nieto fell victim to the U.S intelligency operations, as his emails were read, according to a document dated June 2012.