ISIS terrorist in Syria (file)
ISIS terrorist in Syria (file)Reuters

A US man was sentenced to more than 20 years in prison after he pleaded guilty to supporting the extremist Islamic State group, authorities said Wednesday.

Donald Ray Morgan was arrested last year and charged over supporting and attempting to join the radical group, according to AFP

Morgan traveled to Lebanon but was unable to cross the border into Syria, prosecutors said.

He was a "threat to national security," said FBI agent John Strong in North Carolina, where the sentence was handed down by a federal judge.

Prosecutors said Morgan frequently promoted "violent terrorist activities" and ISIS in social media.

The 44-year-old was arrested at JFK International Airport in New York last year on an indictment for possessing a firearm as a convicted felon.

Morgan's guilty plea for possessing and selling an assault rifle in 2012 following a felony conviction was factored into his 20-year sentence.
Convicted felons are prohibited from owning firearms in the US.

ISIS controls swathes of territory in Iraq and Syria and the US is leading an air campaign to try and destroy the group.

The extremist group known for its brutality has motivated a number of supporters in the US with its radical ideology. US officials said an attempted attack in Texas earlier this month was "inspired" by ISIS, although the group claimed responsibility for the attack. 

"We will continue to do everything we can to shine a light on the false allure of violent extremism and protect innocent people from terrorist
activity, whether inside or outside the United States," US Attorney Ripley Rand said in a statement.