An attack that shocked the world – at least 33 children killed in rebel-held northern Yemen when an air strike by the Saudi-led coalition hit their school bus.

The coalition intervened in 2015 to support the internationally recognised government against Houthi rebels, who are allied with Iran.

Many civilian deaths in Yemen go unreported but with rare footage from the ground, Orla Guerin tells the story of a school trip that ended in disaster, and the children and families still reeling in the aftermath.