"WASHINGTON (Reuters) - Three months before the Sept. 11 attacks on America, John Walker Lindh learned that Osama bin Laden had sent people to the United States to carry out suicide missions, according to the U.S. Justice Department.

Walker, the 20-year-old Californian who joined Taliban fighters in Afghanistan last year, met bin Laden several times while at a training camp for al Qaeda fighters where he learned to use explosives and a variety of weapons.

In a criminal complaint filed on Tuesday, charging Walker with aiding a terror group and conspiracy to kill Americans, the U.S. Justice Department gave the most detailed version of Walker's alleged links to bin Laden and his al Qaeda network.

The United States has blamed bin Laden and al Qaeda for the Sept. 11 attacks on the Pentagon and the World Trade Center that killed nearly 3,300 people.

George Harris, a San Francisco attorney hired by the family, said on Tuesday that Walker had not been given an opportunity to speak with a lawyer.

The Justice Department complaint, based on interviews with Walker after he was captured in Afghanistan in December, spells out a trajectory that began when the American converted to Islam in 1997.

It said that Walker stayed with al Qaeda despite knowing that bin Laden ordered the attacks that killed thousands of people. He even expected additional attacks to follow ... Because of his lack of language skills, Walker was assigned to bin Laden's al Qaeda group and ordered to attend the al-Farooq al Qaeda training camp, according to the complaint.

``Walker ... stated that he knew at the time that bin Laden and al Qaeda were 'against America and the government of Saudi Arabia' and that al Qaeda's purpose was to fight Americans,'' the complaint said.

And at that training camp, Walker apparently learned of possible attacks on the United States.

``Within the first several weeks of his arrival there, in or about early June 2001, Walker learned from one of his instructors that bin Laden had sent people to the United States to carry out several suicide operations,'' the complaint said.

But he stayed on for a seven-week course which included courses in weapons, orienteering, navigation, explosives and battlefield combat, it said.

Walker told U.S. officials that bin Laden visited the camp three to five times and gave lectures. Walker and four other trainees met with bin Laden who thanked them for taking part in jihad (holy war), the complaint said.

Once his training was completed Walker was given several options which included traveling outside Afghanistan to conduct operations against the United States and Israeli targets.

Instead, Walker decided to go to the front lines to fight the Northern Alliance, the complaint said.

It was then that the suicide hijackers slammed planes into the World Trade Center and the Pentagon. Walker said he heard of the attacks by radio shortly after.

``According to Walker, it was his and his comrades' understanding at the time that bin Laden had ordered the attacks and that additional attacks would follow,'' the complaint said.

After Sept. 11, Walker said all of bin Laden's training camps were closed with everyone sent to the front lines to protect bin Laden and defend against possible U.S. attacks. "