A strong earthquake with a preliminary magnitude of between 5.7 and 6.1 has hit the western Greek island of Kefalonia, just over a week after a similar quake damaged dozens of buildings there.
Kefalonia's mayor Alexandros Parisis said the port at the town of Lixouri, the closest to the epicentre, had been seriously damaged and minor injuries reported.
The Athens Geodynamic Institute registered the pre-dawn quake, which struck just after 5am local time, at 5.7, and an epicentre 7.5 miles north west of the island's capital of Argostoli. The US Geological Survey registered a 6.1-magnitude. It is common for different institutes to record slightly different figures and to revise their initial measurements.
Earthquakes have been rattling the island constantly for the past week, after a 5.9-magnitude temblor struck the area on January 26. Since then, thousands of residents have been spending nights with relatives or in ships sent for that reason.
Today's quake was felt on the nearby island of Zakinthos and parts of the western Greek mainland as well as in the capital Athens.
Mr Parisis and seismologists urged people on the island to leave their houses temporarily. Mr Parisis said he was trying to arrange a boat to head to Lixouri, but was being hampered by high winds in the area.
Lixouri, which has been closest to the epicentre of the quakes over the last week, is far from the main town of Argostoli by road but close by sea.
Kefalonia and neighbouring Zakinthos were devastated in 1953 when a 7.2-magnitude temblor struck three days after a 6.4 quake, killing hundreds, injuring thousands and destroying nearly all the buildings on the islands.
Authorities said about 10 people were slightly hurt, mainly by falling objects. Residents calling in to early morning radio and television news shows reported damaged roads and power and water supply cuts in some areas.
Schools on the island have been shut for the past week and had not been scheduled to reopen until Wednesday.
Authorities urged islanders to remain calm and not approach any buildings that appeared damaged.
"This is a critical time, people must be careful and remain calm," said deputy regional governor Antonis Kouris.