Multiple earthquakes are rattling Santorini, a volcanic island in Greece, prompting authorities to dispatch rescuers with tents, a sniffer dog and drones, and to shut schools on four islands. Residents have been warned to avoid indoor gatherings,

Seismic activity is nothing new in the Aegean Sea: Santorini perches on part of the remains of a huge volcano that erupted over 3,000 years ago. But there are fears that the restless earth could trigger property damage – or worse – on one of the most popular Greek islands.