SUPERVOLCANO Campi Flegrei is at a critical stage and scientists have warned that European authorities need to be ready – as experts fear the lives of more than 360,000 people across Europe could be at risk.

Campi Flegrei, located around 11 miles (18 kilometres) southwest of Naples, Italy, has not erupted since 1538, but volcano experts believe it could be building up to another devastating eruption.

Scientists from the University College London (UCL) and the Vesuvius Observatory in Naples have been studying the patterns of unrest since Campi Flegrei's last eruption more than 500 years ago.