Santorini's earthquakes are intensifying as a rare earthquake swarm continues to rattle the Mediterranean's Aegean Sea. The earthquakes are probably caused by faults rather than volcanic activity.

Greek officials are warning those on the popular tourist island destination of Santorini to stay alert in the coming days due to increasing seismic activity which could mean a strong earthquake is possible.

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,