Two British jihadists are believed to have died fighting for Isis (Islamic State) in Kobani, Syria.
Abu Abdullah al Habashi, 21, and Abu Dharda, 20, both from London, are two of 500 Britons believed to have joined the conflict in Syria. Around 27 are understood to have died.
Kurdish fighters have been defending the border town of Kobani from an Islamic State onslaught with the assistance of American and allied air strikes.
Al Habashi has previously made comments on social media supporting the brutal organisation and has appeared in at least two propaganda videos put out by the extremist group.
He grew up in north London in a British-Eritrean family, and converted to Islam when he was 16, the BBC reported.
Al Habashi told the BBC in August that he was at the "forefront" of fighting and claimed to be one of only a few British jihadists who have fought with Islamic State in both Syria and Iraq.
His family tried to convince him to return to his home in London, but he told reporters he was happy in the Middle East and there was "no going back".
Dharda grew up in west London and comes from a British-Somali background. He is understood to have traveled to Syria in December 2013 through Turkey.
A Foreign Office spokesman said: "We are aware of reports of the death of two British nationals in Syria.
"The UK has advised for some time against all travel to Syria, where all UK consular services are suspended.
"As we do not have any representation in Syria, it is extremely difficult to get any confirmation of deaths or injuries and our options for supporting British nationals there are extremely limited."