emwazi , who is originally from london , was planning on joining al-shabaab in africa but changed his mind after his friends were killed amid accusations they were set up by rival group members .
instead he travelled to syria where he joined islamic state and became synonymous with their gruesome beheading videos posted online .
according to a 29-year-old syrian , named only as ayman , emwazi was obsessed with al-shabaab and constantly spoke about the fighting in somalia .