Earthquake in northern Aegean measured at 6.4 Richter, felt in Greece, Turkey and Bulgaria [Update]

An earthquake of 6.4 magnitude struck off the coast of northern Greece on Saturday and was felt as far as neighboring Turkey and Bulgaria but there were no reports of casualties or serious destruction, police and fire brigade officials said.

The US Geological Survey said the quake occurred some 77 km (48 miles) south-southwest of Alexandroupolis, between the islands of Lemnos and Samothrace, at a depth of 10 km (six miles). It downwardly revised its first reading of 7.2.

A duty officer at the Lemnos police precinct said a female British tourist was slightly injured at the airport when part of the ceiling fell, but was treated at the scene and did not require hospitalization. He said no other damage or injuries had been reported.

Greece, at the southeastern end of Europe, is often buffeted by earthquakes. Most cause no serious damage but a 5.9 magnitude quake in 1999 killed 143 people.

In parts of western Turkey on Saturday morning, panicked residents rushed into the streets as a tremor shook buildings, local media reported.

The quake also rattled Turkey's most populous city, Istanbul, as well as the Aegean coastal city of Izmir, according to Reuters witnesses, but there were no immediate reports of damage here as well.

Hurryiet Daily News said that the quake was also felt in the popular tourism province of Antalya.

Earthquakes are a frequent occurrence in Turkey, which is crisscrossed by geological fault lines. In October 2011, more than 600 people died in the eastern province of Van after a quake of 7.2 magnitude and powerful aftershocks.

In 1999, two massive earthquakes killed about 20,000 people in Turkey's densely populated northwest.

Saturday's tremor caused panic in the southern Bulgarian city of Haskovo...