The United States has played down the concerns raised by the resurfacing of Osama bin Laden in a latest video tape, while refusing to comment on his exact status.
"I wouldn't overstate the significance. Obviously, people are always interested in trying to figure out if he's alive, if he's healthy," Michael Chertoff, Secretary of Homeland Security said.
"One of the things you want to do whenever you get a tape is try to determine whether it's been Photoshopped or whether people have integrated different tapes from different types of film into a single broadcast," he said.
"So all of this is going to be looked at by experts. But, again, I wouldn't overemphasise the significance of it," he added.
At the State Department, Deputy Spokesman Tom Casey said: "What his exact status is I don't think anybody knows and I'd certainly leave it to those people in the intelligence community and analysts and others to try and give you any kind of sense of that."
Tapes like the latest one from bin Laden and Ayman al-Zawahiri have been seen before, he said.
"The bottom line is all that does is reinforce the need for all of us to take concrete action to fight extremism and to fight terrorism.
Stressing that US would do "whatever it takes to continue to confront these extremists", Casey said the "fight against extremists in places like Iraq and Afghanistan" would continue.