Iraq: Iraqi Christians Fight for Survival Against IS Militants

Religious leaders warn that Sunni Islamic State militants in Iraq and Syria are trying to ethnically cleanse the region. The ancient Yazidi communities have been particularly targeted for brutal treatment. Christians also are fleeing their homes, prompting fears that religions and sects that have existed for millenia could be wiped out. But as Henry Ridgwell reports from London, many communities are digging in and preparing to fight.