In the summer of 2015, tens of thousands of people left their homes in Syria, Afghanistan and Iraq in the hope of finding a safe haven in Europe. The journeys they took were often hazardous and not everyone reached their destination. In one of the most notorious cases, 71 migrants were found dead in the back of a refrigerated truck on a motorway in Austria. They had all suffocated. Could this tragedy have been prevented? For Crossing Continents, Nick Thorpe speaks to two of the people smugglers who are now serving life sentences in a Bulgarian prison. He visits a man in northern Iraq who lost his younger brother and two children aboard the truck and asks the police in Hungary if they could have acted sooner.

Presenter: Nick Thorpe Producer: Tim Mansel Local Producer: Yana Pelovska Sound mixer: Hal Haines Series editor: Penny Murphy