ATHENS, Feb. 5 (Xinhua) -- An earthquake measuring 5.2 on the Richter scale shook northwestern Greece on Tuesday, without causing injuries or major material damage, according to Greek national news agency AMNA.

Its epicenter was located in the sea region off the town of Preveza, about 300 km from Athens, according to the Institute of Geodynamics, National Observatory of Athens.

The area is quake-prone and Greek seismologists are monitoring the seismic activity, said Efthymios Lekkas, president of Greece's Earthquake Planning and Protection Organization, on local radio Skai.

In the deadliest quake-linked tragedy in the country in recent decades, a 6-magnitude earthquake in Athens caused more than 100 deaths in 1999.