A British jihadist who fought to overturn Libyan dictator Moamer Kadhafi and joined the ranks of the Islamic State group in Syria was sentenced to 10 years in prison Friday.

Mohammed Abdallah, 26, who has dual British and Libyan nationality, joined the "Tripoli Brigade" in 2011 along with his brother, Abdalraouf.

Abdallah's brother was shot and paralysed from the waist down in battle, the trial in London heard.

In 2014, Abdallah headed to Syria with help from his wheelchair-bound brother, who set up a "hub" for would be IS fighters from his home in Manchester, northern England.

He was arrested when he returned to London's Heathrow airport in September 2014.

In 2016, Sky News published files from an IS defector which listed Abdallah as a specialist sniper with expertise in using the "Dushka" -- a Russian-made heavy machine gun.

Abdallah was found guilty on Thursday of possessing a Kalashnikov assault rifle, receiving £2,000 (2,300 euros, $2,700) for terrorism and membership of IS.

Abdallah in court denied pledging allegiance to IS and said he was instead imprisoned by jihadists. He claimed he had only travelled to Syria to donate money to poor people.

But judge Maura McGowan said Abdallah had "bragged" about acquiring weapons and was "totally committed" to signing up to the IS group.

"Your commitment to violence abroad is clear and you have not shown any sign of changing your views or attitudes," she said.

Abdallah's trial was delayed after a terror attack at Manchester Arena in May this year by bomber Salman Abedi, in which 22 people were killed.

Abedi attended the same mosque as the Abdallah brothers and reportedly visited Abdalraouf in prison in the months leading up to the attack.