The US military on Saturday dismisses as "false" an Iranian report that Osama bin Laden had been arrested in Pakistan.
"It's wrong, it's inaccurate, it's false," said Bryan Whitman, a Defense Department spokesman.
The external Pashto-language service of Iranian state radio broadcast the report Saturday quoting an "informed source."
The report, which could not be independently verified, said the arrest took place "some time ago" but gave no further details.
It claimed US officials were keeping news of the arrest secret and were likely to announce it later in the year in order to help US President George W. Bush's re-election chances in November.
"The capture of the al-Qaeda leader was made some time ago, but Bush is intending to announce it at the time of the American presidential election," the report said.
The report said US Defense Secretary Donald Rumsfeld's visit to Afghanistan during the week was intended to follow up on bin Laden's purported arrest in Pakistan.
Bush has meanwhile stepped up the effort to capture bin Laden, using techniques used to capture fallen Iraqi leader Saddam Hussein, The New York Times reported on Saturday.
The Times said the Pentagon will deploy new forces in the effort, at the same time Pakistani leader Pervez Musharraf's resolve to find bin Laden was sharpened after two attacks, perhaps by al-Qaeda.
"Two assassination attempts close together tends to be life-focusing," a senior official in charge of the new effort told the Times.
A covert commando team of Special Operations forces and CIA officers involved in Saddam's capture is heading the effort to track down bin Laden, the Times said.
"With this guy holed up, the more time that goes by, the more likely it is he'll make a mistake," a senior Pentagon official told the paper.
Pakistani Foreign Minister Khurshid Mehmud Kasuri told reporters he could not confirm the reports carried by "international media," and Pakistan's military spokesman Major General Shaukat Sultan told Western reporters, "This report is not correct."
Foreign ministry spokesman Masood Khan also told AFP, "there was no report of bin Laden's arrest from the tribal areas of Pakistan."
Bin Laden is wanted in the US for a series of terrorist acts, including the Sept. 11, 2001, attacks in Washington and New York and is arguably the world's most wanted terrorist. He has released a number of videos calling on supporters to fight the US
Pakistan, a key US ally in war against terrorism, has arrested more than 500 al-Qaeda suspects who fled Afghanistan in the wake of US-led attacks which ousted the hardline Taliban regime in late 2001.