By Bill Gertz

An American Taliban fighter held captive by Marines in Afghanistan has told American officials that al Qaeda's next attack on the United States will take place in days and involve biological weapons, U.S. intelligence officials told The Washington Times.

John Walker Lindh, the Taliban guerrilla captured near Mazar-e-Sharif, said in intelligence debriefings at the U.S. Marine Corps base near Kandahar that "Phase II" of al Qaeda's war against the United States will occur at the end of the Muslim holy month of Ramadan, which ends Sunday.

Mr. Lindh told U.S. intelligence officials that the Ramadan attack will involve the use of biological weapons.

A third phase of al Qaeda's war on the United States will result in the destruction of the entire country, the Islamic convert stated.

The officials said they have questioned the credibility of Mr. Lindh's claim because of his relatively low-level position.

Still, the information was among other intelligence reports that led the Bush administration to issue a public warning last week about a possible terrorist attack, the officials said.

No other details were available about Mr. Lindh's debriefing. However, the intelligence about the impending attack is an indication Mr. Lindh may have been part of the al Qaeda network in addition to fighting on behalf of the Taliban militia.

A CIA spokesman declined to comment.

Gen. Richard B. Myers, chairman of the Joint Chiefs of Staff, said on Sunday that Mr. Lindh was providing information.

"He's been pretty close to the action, and he has provided from the Afghan perspective some useful information," Gen. Myers said on "Fox News Sunday."

"I think the evidence is pretty strong that he was right in the middle of it."

Deputy Defense Secretary Paul Wolfowitz told reporters the American had provided information that has been "very helpful" to the United States, including information on the prisoner uprising at Mazar-e-Sharif that led to the death of CIA officer Johnny "Mike" Spann.

"Obviously the people who really have the information that we really want to get are those top al Qaeda leaders and maybe some of the Taliban leaders and maybe we'll find it in documents in places we are now able to get into," Mr. Wolfowitz said Sunday.

"But I think anyone who knows anything about that organization is a potentially valuable source of information."

The Pentagon has not decided how to handle Mr. Lindh and whether he will be charged with treason.

The U.S. Central Command in Tampa, Fla., said in a statement that Mr. Lindh was being treated as an enemy prisoner of war.

Mr. Lindh, 20, was videotaped as he was interrogated by the CIA officer hours before his death at the hands of rebelling Taliban and al Qaeda prisoners at a fortress near Mazar-e-Sharif. He initially gave his name as Abdul Hamid.

The Marines are using a large green metal shipping container to hold Mr. Lindh at their base in southern Afghanistan, according to pool reports from the base.

Marine Corps spokesman Capt. Stewart Upton said he had no information about Mr. Lindh being held in the container, which is surrounded by barbed wire and Marine guards.

A second Marine spokesman, Capt. David Romley, said later that the only detainee at the camp was Mr. Lindh.

At the Pentagon, Defense Secretary Donald H. Rumsfeld told reporters that valuable intelligence is being collected as U.S. and Afghan opposition forces take over areas once ruled by the Taliban.

"There's documentation being found and discovered and analyzed and translated, so that each day we learn more and know more," Mr. Rumsfeld said. "As more address books are found and phone books are found and computer hard drives are found as people have left areas, clearly our knowledge base is going up."