A third man from Minnesota has now admitted to joining an al Qaeda-linked group in Somalia.

Federal authorities in Minneapolis have unsealed charges against Kamal Said Hassan, believed to be in his early 20s. He pleaded guilty Wednesday afternoon to charges that he lied to FBI agents investigating how more than 20 Somali-Americans were recruited to join the group al-Shabaab, which has ties to al Qaeda and was labeled a terrorist organization by the U.S. government last year.

But, a source told Fox News, Hassan pleaded guilty nearly five months ago to two other charges: providing material support and resources to terrorists, and providing material and resources to a foreign terrorist orgtanization, namely al-Shabaab. Specifically, the source said, Hassan "provided personnel to work under the direction and control of al-Shabaab, knowing that al-Shabaab has engaged in and engages in terrorist activity."

The charges against Hassan are outlined in "criminal informations," which are charging documents often used when a defendant has reached a plea agreement with prosecutors.

Hassan admitted in court on Wednesday that he trained at an al-Shabaab camp in Somalia. According to one source, he told the FBI in early February that, after training with al-Shabaab, he traveled to Yemen without taking any further acts on behalf of al-Shabaab. But, Hassan admitted on Wednesday, he actually did continue to work with members of al-Shabaab in Somalia.

According to another source, Hassan also admitted that he lied about those he interacted with while in Minneapolis and Somalia.

Hassan faces up to 38 years in prison.

This comes nearly a month after authorities unsealed an indictment against two others in the long-running FBI investigation. That indictment was also filed in February, charging Salah Osman Ahmed and Abdifatah Yusuf Isse with providing material support to terrorists. Both pleaded guilty and are cooperating with authorities.

The indictment against Ahmed said he and others traveled to Somalia "so that they could fight jihad" there.

The indictment also charged Ahmed with two counts of making false statements. According to the indictment, he told the FBI in December 2008 that he did not know anyone else on the flight he took to Somalia in 2007.

The fighting in Somalia, which intensified in 2006 after Western-backed Ethiopian forces invaded Somalia, has turned Somalia into a state of anarchy. U.S. officials say if al-Shabaab prevails, Somalia could turn into a haven for al Qaeda and other terrorist groups.