"We've had a chance to look at the imagery. We have people looking at it," said Captain John Kirby, a Pentagon spokesman, noting that the analysts are not "just military personnel," but declining to provide specific details.

Iranian state television earlier aired footage of what it said was the captured drone, showing what appeared to be an RQ-170 Sentinel aircraft with little visible damage.

The footage showed a cream-colored aircraft being examined by two commanders of Tehran's elite Revolutionary Guard Corps, who are in charge of the country's air defenses.

One of them, aerospace unit Brigadier General Amir-Ali Hajizadeh claimed the drone had been captured through a cyber attack.

The RQ-170 Sentinel is a high-altitude stealth reconnaissance drone made by Lockheed Martin whose existence was exposed in 2009 by specialized reviews and later confirmed by the US Air Force in 2010.

Iranian media said late Sunday that the unmanned aerial vehicle was shot down after making an incursion slightly into Iranian airspace. But no precise indication has been given by Iranian officials on where it crashed.

US media said the drone crashed in eastern Iran probably due to a technical fault. The Pentagon has confirmed it lost a drone but declined to acknowledge that it was downed in Iran or that it was operated by the CIA.

Despite US fears that Iran could access and make use of highly-advanced technology found in the drone, an American official said Wednesday that the United States had doubts "the Iranians have the expertise" to exploit the technology found in the wrecked vehicle.

The New York Times reported that the drone was part of a surveillance program that has frequently sent the hard-to-detect aircraft into Iran to map suspected nuclear sites.

The crash came at a time of heightened political tension over Iran's nuclear program, with speculation rife that Israel is mulling air strikes against Iranian atomic facilities, with or without US backing.

The New York Times reported Thursday that the unmanned stealth drone was part of a surveillance program that has frequently sent the hard-to-detect aircraft into Iran to map suspected nuclear sites.

Citing foreign officials and American experts who have been briefed on the effort, the Times said the drone was part of the most secret of many intelligence-collection efforts against Iran, but that the crash effectively blew the program's cover.

The Washington Post said the drone program indicates that US officials believe covert action and economic pressure may be the only means of pressing Iran to abandon its nuclear ambitions.

Citing current and former US officials, the Post said the administration's strategy includes expanded use of remote-controlled stealth aircraft, such as the one that came down in eastern Iran last week.

The report said the effort also includes stepped up sales of bunker-busting munitions, fighter jets and other military hardware to Gulf states as well as Israel to counter a potential threat from Iran.

The officials told the Post the new strategy suggests Washington is losing patience with efforts to negotiate a deal with Tehran to halt its nuclear program suspected of being used to create weapons.

The RQ-170 Sentinel high-altitude stealth drone was on a surveillance mission when it crashed in eastern Iran.

According to the Post, the CIA is thought to have a dozen or so of the batwing-shaped, radar-evading aircraft which can capture a range of intelligence material, including high-resolution images, radiation measurements and air samples.

US officials said that aircraft had been en route to Afghanistan at the time of the crash.

Iran's military claimed it shot down the drone inside its territory near the Afghan and Pakistani borders, and threatened to retaliate for the violation of its airspace. The Pentagon said there was no indication that the drone was shot down.

An identical stealth aircraft to the one lost in Iran reportedly was used by US Navy SEALs in the operation last May that killed Al-Qaeda chief Osama bin Laden in Pakistan.