(AP) Federal authorities have arrested an American Muslim activist who they believe took computer equipment to an al Qaeda terrorist camp in Afghanistan.

A law enforcement official speaking on condition of anonymity said Tuesday that James Ujaama, 36, was arrested Monday night in Denver as a material witness to terrorist activity and flown to Virginia.

The official said the activity that led to Ujaama's arrest was not related to the Sept. 11 attacks.

Another federal official said investigators believe Ujaama may have supplied terrorists in Afghanistan with computer equipment. He said authorities were investigating whether Ujaama also trained at the camp.

Ujaama told the Rocky Mountain News during a jailhouse interview Tuesday that he had never heard of al Qaeda until the Sept. 11 attacks.

"I wasn't planning any terrorist attacks, I'll tell you that — or delivering laptops to terrorists," he said.

Ujaama declined to answer whether he had traveled to Afghanistan, whether he has met with members of the Taliban and where he was on Sept. 11.

"Things get twisted around," he said. "At this point in time, I think it's better to not say anything."

Ujaama has not been formally charged. Holding him as a material witness — someone with possibly important information — allows federal authorities to keep him in custody indefinitely.

Ujaama's mother, Peggi Thompson of Seattle, said her son was arrested at his aunt's home in Denver.

"The FBI came and got him," Thompson told The Associated Press. "There's nothing I can do or anything right now. Nobody's saying anything."

Ujaama's brother, Mustafa, also was briefly detained Monday, she said.

Mustafa Ujaama answered reporters' shouted questions as he left his aunt's Denver home Tuesday.

When asked if he was linked to terrorism, Mustafa Ujaama said, "No. Why (do) you ask me that? Of course not. I'm a veteran. I'm an American citizen.

"I've never even heard of al Qaeda," he said. "My brother is not a terrorist and neither am I."

The brothers were born James Ernest Thompson and Jon Thompson and grew up in Seattle. Some community leaders there have applauded their work to rid their neighborhood of drugs and prostitution by recruiting former gang members and others into the local mosque, Dar-us-Salaam.

That mosque, now defunct, is under scrutiny for possible links to Osama bin Laden's al Qaeda terrorist network.

James Ujaama has published four books, his brother said. The Denver Public Library had three books listed by him — "Coming Up," "Entrepreneur Basics 101," and "Young People's Guide to Starting a Business" — but they're not at the library now. Two are listed as out of print on the Amazon.com Web site.

News reports say James Ujaama worked on a British Web site that advertised the "Ultimate Jihad Challenge," a paramilitary training course in the United States. British authorities shut the site down following the Sept. 11 attacks. He also runs a Web site called stopamerica.org, which opposes U.S. foreign policy.

James Ujaama said the FBI had been following him and tapping his phones since he moved from London to Denver last month. He said that when authorities descended on his aunt's house, he went outside and started taking pictures.

"They came flying toward me, and said, `Get your hands on the ground, get down, get down,"' he recalled. "They've got M-16 rifles drawn, pointing them at my family. I'm saying, `Man, this is crazy. It looked like Beirut up there."'