An earthquake measuring 4.7 on the Richter scale jolted southern Bulgaria shortly after 3 p.m. on Tuesday. The epicentre was registered 350 km southeast of Sofia.
The tremor was felt in the capital Sofia, the second-biggest town of Plovdiv, Haskovo, Dimitrovgrad, Simeonovgrad, Kardhzli and Harmanli.
No damages or casualties were reported.
Meanwhile moderate-sized earthquakes struck northwestern Turkey and Greece.
The quake measuring 5.1 on the Richter scale was centred in the Saros Gulf in the Sea of Marmara near the city of Canakkale, the Kandili Observatory in Istanbul said.
Greece was jolted by a quake, measuring 4.9 on the Richter. The tremor was felt in the Greek part of the Thracian valley. The epicenter of the earthquake was registered some 324 kilometers northwester of the Greek capital.
There were no immediate reports of casualties or damage.