A leading computer security firm has linked some of the software code in the powerful Flame virus to the Stuxnet cyber weapon, which is believed to have been used by the United States and Israel to attack Iran's nuclear program.

Eugene Kaspersky, chief executive of Moscow-based Kaspersky Lab, which uncovered Flame last month, said his researchers have since found that part of the Flame program code is nearly identical to code found in a 2009 version of Stuxnet.

The new research could bolster the belief of many security experts that Stuxnet was part of a massive U.S.-led cyber program that is still active in the Middle East and perhaps other parts of the world.

Although Kaspersky did not say who he thought built Flame, news organizations including Reuters and the New York Times have previously reported that the United States and Israel were behind Stuxnet, which was uncovered in 2010 after it damaged centrifuges used to enrich uranium at a facility in Natanz, Iran.

Instead of issuing denials, authorities in Washington recently launched investigations into the leaks about the highly classified project.

On Stuxnet and Flame, "there were two different teams working in collaboration," Kaspersky said at the Reuters Global Media and Technology Summit in London on Monday.

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