DOHA, Qatar — A Qatari man declared an enemy combatant by the Bush administration after the Sept. 11, 2001, attacks and imprisoned over links to al-Qaida has returned home to the Gulf nation after quietly being released by U.S. authorities.

Ali al-Marri was arrested in December 2001 while attending graduate school in central Illinois. He was held without charge for nearly six years in a Navy brig in South Carolina before eventually pleading guilty and receiving a sentence of just over eight years behind bars.

Al-Marri’s nephew, Saleh Garallah Kahlah al-Marri, said Sunday that his uncle returned home to the small energy-rich country the previous evening and was greeted by representatives from the Qatari interior and foreign ministries.

“He is in high spirits,” Saleh al-Marri said. The nephew thanked Qatari officials for their help in getting al-Marri back home, saying they made “tremendous efforts” to do so.

Al-Marri will not be making comments to the media for now because “we want to give him an opportunity to reintegrate into society,” the nephew said.

Al-Marri was sentenced to eight years in prison in 2009 after pleading guilty to conspiring to provide material support or resources to a foreign terrorist organization. He was expected to serve less than six years in consideration for time spent behind bars before and after his stay in the brig.