WASHINGTON - After 45 days of interrogation, American Taliban fighter John Walker Lindh is headed back to the United States to stand trial, a U.S. official said on Tuesday.

The official, speaking on condition of anonymity, said Walker left Afghanistan by plane on Tuesday and was expected to be in the United States on Wednesday.

Walker, a 20-year-old Californian who goes by his mother's name, was charged on Jan. 15, with conspiring to kill U.S. nationals in the war in Afghanistan and with providing support to Osama bin Laden's al Qaeda network.

If convicted, he could be sentenced to life imprisonment.

Al Qaeda is blamed by Washington for the Sept. 11 attacks on the United States that killed more than 3,000 people.

In the criminal complaint against Walker, the U.S. Justice Department said he stayed with al Qaeda despite knowing that bin Laden ordered the attacks and said he even expected additional attacks to follow.

Pentagon and Justice Department officials on Tuesday declined comment on U.S. network news reports that Walker was due to land outside Washington.

"We don't talk about any transportation or movement until it's completed," said a Pentagon spokeswoman.

U.S. officials have said Walker would be handed over to the Department of Justice to face trial in federal court in Alexandria, Virginia.

Officials from the U.S. District Court in Alexandria said on Tuesday evening they had not yet been advised of a date for Walker's initial court hearing. So far, a judge has not been assigned to the Walker case.

Walker had been held aboard the U.S. warship Bataan in the Arabian Sea. He was captured after an uprising among Taliban fighters at a prison outside the northern Afghan city of Mazar-i-Sharif. CIA agent Mike Spann was killed during the uprising.

Walker, who converted to Islam in 1997 at age 16, joined Taliban fighters in Afghanistan last year.

Also facing trial in Alexandria is Zacarias Moussaoui, a French citizen of Moroccan descent, on charges of complicity in the Sept. 11 attacks. Nampa-Reuters