Secretary of State Colin Powell on Monday repeated Washington's denials that US forces had apprehended al Qaeda terrorist mastermind Osama bin Laden.
"I deny it, he has not been captured," Powell told NBC television.
"This rumour started somewhere about the middle of last week, got picked up and was denied by the Pentagon," he said, adding, "don't know where he is or what he might be doing."
Powell said he also could not confirm reports that US authorities have stepped up their efforts to capture bin Laden, who is believed to have authored the September 11, 2001 attacks on Washington and New York that killed nearly 3,000 people.
"I would hope that is the case, but I can't confirm it," Powell said.