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.

More than 200 tremors have been registered since Friday between the Greek volcanic islands of Santorini and Amorgos.

ATHENS (Reuters) -Greek authorities have warned of an increase in seismic activity around the Aegean tourist island of Santorini, advising people to avoid four ports, empty their pools, refrain from gathering in indoor spaces and shut schools on Monday.

Greece sits on multiple fault lines and is often rattled by earthquakes. Santorini is visited by about three million people annually, including many British tourists. One of the largest volcanic eruptions in history, around 1600 BC, formed the island in its current shape, while the last eruption in the area occurred in 1950.

Schools on the Greek island of Santorini have been told to close on Monday in response to an increase in seismic activity in recent days. Authorities have also advised against "large gatherings in enclosed spaces" across the island - a popular tourist destination known for its whitewashed buildings and blue domed churches.

Authorities on Greece’s tourist island of Santorini ordered school closures on Sunday as the island braced for further tremors after more than 200

Greece's tourist island of Santorini on Sunday braced for the prospect of more tremors after more than 200 small earthquakes shook the site of one of the largest volcanic eruptions in recorded history,