The quake occurred at 2006 GMT and its epicentre was 57km northeast of Athens, according to the European-Mediterranean Seismological Centre. Its focal depth was initially estimated at 2km.
Earlier on Tuesday, an earthquake measuring 4.7 on the Richter scale shook the island of Evia, in central Greece, damaging old buildings in the area and forcing authorities to shut down schools protectively. Smaller-scale tremors followed.

The moon behind the ancient temple of the Parthenon in Athens.