Tehran says experts have learned how to rebuild and extract data from the unmanned spy plane it captured in December.

Iran says it has reverse-engineered a US spy drone captured by its armed forces last year and has begun building a copy.

General Amir Ali Hajizadeh, chief of the aerospace division of the powerful Revolutionary Guards, related on Sunday what he said were details of the aircraft’s operational history to prove his claim that Tehran’s military experts had extracted data from the US RQ-170 Sentinel captured in December in eastern Iran.

Among the drone’s past missions, he said, was surveillance of the compound in northwest Pakistan in which Osama bin Laden lived and was killed.

Tehran has flaunted the capture of the Sentinel, a top-secret surveillance drone with stealth technology, as a victory for Iran and a defeat for Washington in a complicated intelligence and technological battle.

US officials have acknowledged losing the drone. They have said Iran will find it hard to exploit any data and technology aboard it because of measures taken to limit the intelligence value of drones operating over hostile territory.

US Senator Joe Lieberman, a leading voice on defense matters, expressed skepticism at Iran’s claim.

“There is some history here of Iranian bluster particularly now when they’re on the defensive because of our economic sanctions against them,” he said.

Hajizadeh told state television that the captured surveillance drone is a “national asset” for Iran and that he could not reveal full technical details. He did provide some samples of the data that he claimed Iranian experts had recovered.

‘Data recovered’

“There is almost no part hidden to us in this aircraft. We recovered part of the data that had been erased. There were many codes and characters. But we deciphered them by the grace of God,” Hajizadeh said.

Hajizadeh claimed that the drone flew over Bin Laden’s compound in Pakistan two weeks before the al-Qaeda leader was killed there in May 2011 by US Navy SEALs. He did not say how the Iranian experts knew this.

Before that, he said, “this drone was in California on October 16, 2010, for some technical work and was taken to Kandahar in Afghanistan on November 18, 2010. It conducted flights there but apparently faced problems and [US experts] were unable to fix it,” he said.

Hajizadeh said the drone was taken to Los Angeles in December 2010 where sensors of the aircraft underwent testing at an aerospace factory.

“If we had not achieved access to software and hardware of this aircraft, we would be unable to get these details. Our experts are fully dominant over sections and programmes of this plane,” he said. “It’s not that we can bring down a drone but cannot recover the data.”

There are concerns in the US that Iran or other states may be able to reverse-engineer the chemical composition of the drone’s radar-deflecting paint or the aircraft’s sophisticated optics technology that allows operators to identify suspects from thousands of metres in the air.

Media reports claimed this week that Russia and China have asked Tehran to provide them with information on the drone but Iran’s defense ministry denied this.