Thousands of foreign fighters could be fighting with extremist groups in Syria. There is fear that these fighters could come back to launch terror attacks on their own homeland, posing an increasing global threat.

Douglas McCain, a 33-year-old American, died in battle this weekend in Syria. He was fighting for the Islamic State extremist group. His death comes 10 years after his conversion to Islam.

McCain’s death is a reminder of a growing problem that many countries have. Thousands of foreign fighters from 50 countries are engaged in Syria and affiliate themselves with Islamic extremist groups.

CCTV America’s Jim Spellman reports.