Daniel Patrick Boyd developed a following in his local Muslim community as believers learned about his time waging war against the Soviets in Afghanistan, and he used that stature to tell young followers about the need for violent jihad, prosecutors said Wednesday.

Boyd has now acknowledged his involvement in supporting and plotting terrorism, pleading guilty in federal court to a pair of charges as prosecutors laid out new details of his activities. The plea provided the government with a crucial conviction against what they have described as a ringleader who guided a Raleigh-area group that sought to wage war against nonbelievers.

Prosecutors said the case illustrated the growing concern of homegrown terrorism.

"The radicalization of Muslims here in our country is a very serious threat," U.S. attorney George Holding said.

More than a half-dozen others have been charged in the case, and most of them were younger than 25 when they were indicted in July 2009, including two of Boyd's sons — Zakariya and Dylan. A trial is scheduled for September. Prosecutors said Boyd is cooperating in the case.

With his once-flowing beard shaven clean and hair slicked back, Boyd tearfully answered a judge's yes-or-no questions before finalizing his guilty plea. He smiled at a few family members in the audience. They declined to comment after the hearing, though his wife has said in the past that he was not involved in terrorism.