It was the strongest earthquake not only in this year, but also in the last 15 years after a magnitude 6 earthquake on Oct. 27, 2004.
The earthquake was strongly felt in the capital city of Bucharest and many other cities in Romania.
There were no immediate reports of injuries in the epicenter area.
The epicenter of the earthquake, with a depth of 150 km, was determined to be near Nehoiu, some 120 km northeast of Bucharest.
Some 30 other seismic events took place in Romania in October, with magnitudes between 2.0 to 3.5.
The Vrancea seismic zone, including the eastern counties of Vrancea and Buzau, as well as surrounding mountains, is one of the most active seismic areas in Europe. It is known for its intermediate-depth (70-200 km) earthquakes, which can reach a magnitude of 7.0 to 7.8.
In March 1977, a major earthquake killed over 1,000 people in Romania and damaged thousands of buildings.
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