The strongest earthquake recorded was magnitude 4.6 at 3:55 p.m. Sunday, at a depth of 14 kilometers (9 miles), the Athens Geodynamic Institute said.

A series of earthquakes near the Greek island of Santorini have led authorities to shut down schools, dispatch rescue teams with sniffer dogs and send instructions to residents including a request to drain their swimming pools.

Schools on the Greek tourist island of Santorini will remain closed on Monday after more than 200 small earthquakes shook the region, civil protection authorities announced. Santorini is one of the most popular Greek islands for tourists.