A bell is seen on the ground near a church following an earthquake in Norcia, Italy, October 30, 2016. [Photo/Agencies]

Earlier this week, the same areas had been hit by two temblors measuring a magnitude of 5.4 and 5.9, respectively.

On Aug 24, another 6.0-magnitude earthquake had struck villages and towns of central Lazio and Marche regions, only slightly to the south from Sunday's epicenter. That first temblor killed 298 people, and injured some 400 others.

After such sequence, the number of people forced to leave their homes might now amount to several tens of thousands, according to authorities.

"This latest 6.5 quake has changed the scenario and the scale of the emergency," Curcio stressed. "We need time to adjust our assessment, but we will keep following the path of close coordination with local and regional authorities we have undertaken since Aug. 24."

Authorities and relief teams also explained the absence of victims in such a strong quake had been possible thanks to one of the main factors: many people had already left their houses after the previous temblors earlier this week.

Although no victims were claimed, the event proved disastrous for already deeply affected communities in central Italy.

People were under much strain, as the earth has kept trembling for months. Indeed, the INGV has registered some 18,000 aftershocks since Aug. 24.

Some 15,000 power lines were cut, and many roads in central Italy were disrupted, according to the civil protection authorities. A main highway connecting Rome to the affected areas was cut off due to landslides, and some provincial roads were impassable, creating difficulties for relief efforts.

Several buildings were severely hit, and other structures already damaged by the two previous earthquakes this week, including the 14th-century San Benedetto Basilica in Norcia, were almost flattened.