Desperate Syrian family hopes to reunite after fleeing Raqa

In four years, Mohammad al-Hassan only heard his son's voice once: when the young Syrian soldier called a radio show to send regards to his family trapped in jihadist bastion Raqa. The 62-year-old and his wife Nazira, who never left their home town in northern Syria during years of Islamic State group rule, have seen their family torn apart by the country's complex war.