CAIRO, Egypt — The latest audio tape by Usama bin Laden may be an attempt by the Al Qaeda chief to regain the spotlight for his terror network and raise his profile after being overshadowed by insurgents in Iraq, terrorism experts said Wednesday.

Intelligence experts said a technical analysis of the tape, which was posted on the Internet Tuesday, showed the tape was probably authentic.

On the tape, bin Laden said that neither Zacarias Moussaoui — the only person convicted in the United States for the Sept. 11 attacks — nor anyone held at Guantanamo had anything to do with the Al Qaeda operation.

"I am the one in charge of the 19 brothers and I never assigned brother Zacarias to be with them in that mission," he said, referring to the 19 men who hijacked the four aircraft used in the Sept. 11, 2001, attacks.

The tape is the third issued by bin Laden this year — a sharp increase in the volume of propaganda issued by Al Qaeda since August, according to terror experts such as Ben Venzke, head of IntelCenter, a private U.S. company that monitors militant message traffic and provides counterterrorism intelligence services to the U.S. government.

"Al Qaeda messaging volume levels are at the highest now than at any point since the group's inception," Venzke said.

Rohan Gunaratna of the Institute of Defense and Strategic Studies in Singapore said the increase in propaganda was apparently bin Laden's attempt to compensate for his group's loss of ability to mount attacks. The U.S.-led war on terror apparently has severely disrupted the portion of Al Qaeda directly under bin Laden's control, he said.

That has allowed the head of Al Qaeda in Iraq, Abu Musab al-Zarqawi, to capture the spotlight on the world terrorism stage watched by militant sympathizers, Gunaratna told The Associated Press in a call from Singapore.

"The jihadis are increasingly looking to al-Zarqawi, who is on the ground and every day is killing Americans in Iraq," Gunaratna said. "Al-Zarqawi is stealing the thunder of bin Laden."

By stepping up his propaganda, Gunaratna said he believed "bin Laden is trying to maintain his eminence in the global jihad."

Moussaoui, a 37-year-old Frenchman and admitted AL Qaeda member, was sentenced to life in prison earlier this month after a jury in the United States ruled that he was responsible for at least one death on Sept. 11.

On the tape, bin Laden said to Americans: "Since Zacarias Moussaoui was still learning how to fly, he wasn't No. 20 in the group, as your government has claimed."

Bin Laden said Moussaoui's confession of involvement in Sept. 11 was "void," and the result of pressure during imprisonment.

"Brother Moussaoui was arrested two weeks before the events, and if he had known something — even very little — about the Sept. 11 group, we would have informed the leader of the operation, Mohammad Atta, and the others ... to leave America before being discovered," bin Laden said.

Bin Laden also said that none of the hundreds of terror suspects held at the U.S. prison at Guantanamo Bay, Cuba, was involved in the Sept. 11 attacks — and said most had no ties to Al Qaeda.

"Our brothers in Guantanamo ... have no connection whatsoever to the events of Sept. 11," he said, claiming they were jailed to justify the cost of the war on terror.

But he did say two of the detainees were linked to the Sept. 11 attacks. "All the prisoners to date have no connection to the Sept. 11 events or knew anything about them, except for two of the brothers," bin Laden said. But he did not provide names or elaborate further.

The audio message, which is less than five minutes long, was transmitted with a still photo of bin Laden.

In a tape aired on Arab television in March, bin Laden denounced the United States and Europe for cutting off funds to the Hamas-led Palestinian government, accusing them of leading a "Zionist" war on Islam, and urged followers to fight any U.N. peacekeeping force in Sudan.

In January, bin Laden said in an audiotape that Al Qaeda was preparing new attacks in the United States but offered a truce — though his lieutenant Ayman al-Zawahiri later issued a video saying Washington had refused to take the offer.

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