A strong 6.8-magnitude earthquake struck off Greece on Friday, according to the US Geological Survey (USGS) with no immediate reports of casualties so far. 

The quake, with a depth of 16.6 kilometers, took place at 35 kilometers west of Lithakia, a village in the southern part of the tourist island of Zakynthos. 

The tremor was reportedly felt in Athens, and as far away as Italy, Malta, Albania and Libya, and has caused damages and electricity cuts, reported Greek national news agency AMNA.

"We have been in contact with the local authorities to see where there is damage," Reuters reported, citing the spokesman Spyros Georgiou. "The efforts were focused on villages with old buildings," Georgiou added.