A prominent U.S. newspaper is reporting that U.S. President Barack Obama – in his first months in office – secretly ordered sophisticated attacks on the computer systems that run Iran's main nuclear enrichment facilities.

The New York Times cited anonymous sources close to the program who called the order a major expansion of America’s first sustained use of cyberweapons. The program reportedly started during the George W. Bush administration.

Iran says its nuclear program is for peaceful use. But the West and Israel fear Iran is covertly developing nuclear weapons capability. Foreign nations are using sanctions to push Iran into compliance with international demands that it allow U.N. inspectors into its nuclear sites.

Iran has blamed computer attacks on Israel and the West, which it accuses of trying to sabotage the Iranian nuclear program. But no one has claimed responsibility.

A computer virus called Flame was recently discovered in Iran and other Middle Eastern countries. Iranian officials have warned that Flame is potentially more harmful than a previous virus, Stuxnet, but said this week that an antivirus program was developed.

The Times reported that Obama increased the computer attacks even after part of the program became public in 2010 because of an error that allowed a computer virus to escape Iran’s Natanz plant and travel around the world on the Internet.

Computer experts gave that virus the name Stuxnet, which is believed to have set back Iran’s nuclear program by temporarily taking out many centrifuges used to purify uranium.

The Times based its account on interviews over the past 18 months with current and former American, European and Israeli officials involved in the cyber program, as well as outside experts.

The Times story came as satellite images obtained this week by a U.S. research group suggested Iran may be trying to wipe traces of nuclear weapon testing from a key military site.

The U.S.-based Institute for Science and International Security (ISIS) said the images, published on its website Thursday, indicate two small buildings at the site as the suspected testing chamber have been razed.

ISIS said satellite images were taken May 25 and support other images from April that indicated Iran had begun clean-up activities at its Parchin military complex. It also said the new images “raise further concerns of Iranian efforts to destroy evidence of alleged past nuclear weaponization activities.”

Western powers suspect Iran has engaged in atomic weapons research at the Parchin complex and the International Atomic Energy Agency has been trying to negotiate access to the site. Tehran says Parchin is a conventional weapons facility.