British man Abu Layth al-Khurasani was killed in the past few days fighting for Islamist forces in Syria.
His friends paid tribute to his "martyrdom" on Twitter and Instagram.
He sent his last tweet on January 30th, writing: "Turkey are now actively aiding FSA on the borders of Al Ra'i, there are two Turkish tanks guarding a checkpoint close to the town."
More top news
How is Sainsbury's positioned to tackle the challenges of low-cost rivals and changing shopping habits?
The head of football's anti-discrimination body Kick It Out has responded to attacks by QPR defender Rio Ferdinand in his autobiography
Prime Minister David Cameron and his wife Samantha surprised diners in Solihull by dropping into fast food chain Five Guys for burgers.