Three earthquakes measuring 4.3, 4.0 and 4.0 on the Richter scale were recorded during the night in the sea area 18 to 24 kilometers south-southwest of Amorgos, according to data released by the Geodynamic Institute of the National Observatory of Athens.

All three earthquakes are described as 'light' by the Institute.

According to the Committee for Risk and Crisis Management of the National and Kapodistrian University (NKUA), "more than 2,500" tremors have been recorded in the Santorini volcanic complex since June adding that "this does not exclude the possibility these are features of a pre-seismic sequence." 

See also:

Third raft of emergency measures due to seismic activity near Santorini - New quakes in Amorgos