Mamunur Roshid
Assad Uzzaman was one of five British extremists who slipped under the radar in Turkey to join Isis

A British Muslim from Portsmouth who joined Islamic State (Isis) with four friends has been killed in Syria.

Assad Uzzaman, 25, was the final member of the group that was filmed leaving Gatwick in 2013 and called itself the 'Britani Brigade Bangladeshi Bad Boys'.

The group said that they were going on a Turkish beach holiday before slipping over the border to Syria to fight for IS. Since then, four of the men have been killed and a fifth, Mashudur Choudhury, is in prison in the UK after returning to the country after just a few months.

Uzzaman's friends Mamunur Roshid, 24, and Mehdi Hassan, 19, and were both killed in October 2014. The fifth, Muhammad Hamidur Rahman, 25, was one of the first Britons to be killed in Syria.

His death was announced on Twitter by Shiraz Maher, a senior fellow at The International Centre for the Study of Radicalisation and Political Violence (ICSR), a group that monitors the activities of extremists. He also speculated that Uzzaman could be the 50th Briton killed fighting for IS, but that was not confirmed as the nationality of one of the men is still not clear.

"The last of the Portsmouth cluster of fighters with Islamic State, Assad Uzzaman (Abu Abdullah) has died."

Although IS uses British fighters in recruitment and propaganda videos, they are often used either as suicide bombers or on the front line due to their inexperience, compared to the often battle-hardened Iraqi or Syrian fighters who have served in other conflicts.