Huge magma reservoir growing under Santorini

A giant 'balloon' of magma has been welling up under the Greek island of Santorini, raising it an extra five and a half inches above the sea.

Volcanic activity detected on Greek island

The volcanic Greek island of Santorini - named by the BBC as the world's best island last year - appears to be working up to an eruption, its first for over 60 years.