Adnan Shukrijumah, 35, is shown in this undated combination of photos provided by the FBI. [Agencies]

Shukrijumah, who trained at al-Qaida's Afghanistan camps in the late 1990s, was labeled a "clear and present danger" to the US in 2004 by then-Attorney General John Ashcroft. The US is offering a $5 million reward for information leading to his capture and the FBI also is releasing an age-enhanced photo of what he may look like today.

It's natural he would focus on attacking on the US, LeBlanc said.

"He knows how the system works. He knows how to get a driver's license. He knows how to get a passport," LeBlanc said.

Shukrijumah's mother, Zurah Adbu Ahmed, said Thursday on the front stoop of her small home in suburban Miramar, Fla., that her son frequently talked about what he considered the excesses of American society -- such as alcohol and drug abuse and women wearing skimpy clothes -- but that he did not condone violence. She also said she has not had contact with her son for several years.

"This boy would never do evil stuff. He is not an evil person," she said. "He loved this country. He never had a problem with the United States."

LeBlanc said the new charges were brought after the New York subway bomb suspects identified him to investigators as their al-Qaida superior. The New York suspects provided other key information about his al-Qaida status.

"It was basically Adnan who convinced them to come back to the United States and do this attack," LeBlanc said. "His ability to manipulate someone like that and direct that, I think it speaks volumes."

Before turning to radical strains of Islam, Shukrijumah lived in Miramar with his mother and five siblings, excelling at computer science and chemistry courses while studying at community college. He had come to South Florida in 1995 when his father, a Muslim cleric and missionary trained in Saudi Arabia, decided to take a post at a Florida mosque after several years at a mosque in Brooklyn, N.Y.

At some point in the late 1990s, according to the FBI, Shukrijumah became convinced that he must participate in "jihad," or holy war, to fight perceived persecution against Muslims in places like Chechnya and Bosnia.

That led to training camps in Afghanistan, where he underwent basic and advanced training in the use of automatic weapons, explosives, battle tactics, surveillance and camouflage.

"What's dangerous about an individual that understands the US is he may have a better sense of our security vulnerabilities and insights into how to terrify the American people using smaller attacks for large, political impact," said Brian Fishman, a counterterrorism research fellow at the New America Foundation. "This increases the risk of attacks outside traditional places we normally worry about like New York and Washington."

Shukrijumah was born in Saudi Arabia. He is a citizen of Guyana, a small South American country where his father was born. His father died in 2004.