The number of refugees and migrants arriving in Greece this year has surpassed the half-million mark, the UN Refugee Agency (UNHCR) said on Tuesday.

The agency said that the current spike in arrivals to Greece from countries including Syria and Afghanistan, was putting huge pressure on the Greek islands.

UNHCR’s Ron Redmond has been to the island of Lesvos, where the majority of people are arriving.

Daniel Dickinson asked him for an update.