Repeated earthquakes are rattling Greece’s volcanic island of Santorini. The quakes are prompting authorities to dispatch rescuers with tents, a sniffer dog and drones and to shut down schools on four islands.

Schools have been shut and public gatherings are being discouraged on the Greek island of Santorini as local authorities put the popular tourist spot on high alert for a big earthquake, following scores of small temblors over the last two days.