Syria conflict: Anti-IS alliance eyes 'capital' Raqqa

A US-backed alliance of Syrian Kurdish and Arab fighters has begun a campaign to expel Islamic State (IS) militants from the countryside north of Raqqa.

The Syrian Democratic Forces (SDF), which is believed to have about 30,000 personnel, said the aim was to prevent attacks on nearby towns it controlled.

Does this mean IS losing influence and territory and is it likely Raqqa could soon be recaptured?

Frank Gardner reports