Short video message gives simple reason behind going to Syria . Konstandinos Erik Scurfield was killed fighting Islamic State on Monday . Former Royal Marine is first UK national to be killed battling ISIS in Syria . Kurds' son told friends he went to region for humanitarian work . Former commando 'frustrated ' by lack of government action against ISIS . Comrades from the group he fought with said he was a 'disciplined warrior ' They said he wanted to be buried beneath an olive tree in Syria . Grieving parents say he lived with 'love , courage , conviction and honour '
Short video message gives simple reason behind going to Syria . Konstandinos Erik Scurfield was killed fighting Islamic State on Monday . Former Royal Marine is first UK national to be killed battling ISIS in Syria . Archaeologists' son told friends he went to region for humanitarian work . Former commando 'frustrated ' by lack of government action against ISIS . Comrades from the group he fought with said he was a 'disciplined warrior ' They said he wanted to be buried beneath an olive tree in Syria . Grieving parents say he lived with 'love , courage , conviction and honour '