Washington, Dec 17 - The Central Intelligence Agency (CIA) has denied that Pakistani-American David Coleman Headley, a key suspect in the 26/11 terror attacks, was its agent at any point of time.

"I can't comment on an ongoing investigation, but any suggestion that this individual worked for the CIA is flat wrong," said CIA spokesperson Marie E. Harf.

Headley has been charged in a federal court with conspiring to commit terror attacks outside the US and providing material support to terrorist organisations.

Media reports in India and the US quoting unnamed officials have said that Headley could have been a "double agent", working for the CIA as well as Pakistani terror groups including Lashkar-e-Taiba (LeT), which carried out the Mumbai attack that killed nearly 170 Indians and foreigners.

Headley, now in a Chicago jail, was arrested by the Federal Bureau of Investigation Oct 3 while planning to go to Pakistan via Philadelphia.

Meanwhile, US strategic think tank Stratfor says it is difficult to establish if Headley was indeed a double agent.

"At present, it is very difficult to ascertain if Headley was a double agent who was really reporting to LeT and the Harkat-ul-Jehad-al-Islami (HUJI) the entire time he was ostensibly working for the US government or if he was merely a rogue informant who was playing both ends against the middle for his own personal benefit," it said.

"Such rogue sources have been seen in jihadist cases before. If Headley was either a double agent or a rogue source, there may be some significant blowback for the US government as further revelations are made about the case."

US authorities say that in order to conduct surveillance for the Mumbai attacks, Headley made five extended trips to the city between September 2006 and July 2008.

During each trip, Headley reportedly took pictures and made videos of various targets, including those attacked in November 2008.

He also reportedly travelled to Pakistan after each trip to brief his co-conspirators there and to provide them with his maps, sketches, photos and videos. (IANS)