Reports of the deaths of two British citizens in Syria have reportedly come "via a British fighter" who has joined up with Islamist group ISIS.
Shiraz Maher, an expert on Islamic radicalism from King's College London, wrote on Twitter that the two had been fighting against Jabhat al-Nusra, another Islamist group.
"It appears two British citizens have died in Syria while fighting for ISIS. They were fighting Jabhat al-Nusra at the time," Mr Maher wrote.
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