Residents on the popular island of Santorini have experienced hundreds of earthquakes this week while researchers have revealed a new magma chamber underneath the Kolumbo submarine volcano.

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.

Several more earthquakes have struck waters around the Greek island of Santorini just hours after authorities there declared a state of emergency. The tourist hotspot has been rocked by days of seismic activity with thousands of earthquakes recorded since last Friday.