REUTERS/Emiliano Grillotti
The Guardian and other outlets say 5 are confirmed dead. However, as of 8.25 a.m. BST, the BBC said the death toll has risen to 13.
The quake caused serious damage to a number of towns and villages but did not seem to have hit heavily populated areas.
The worst hit towns were believed to be Accumoli, Amatrice, Posta and Arquata del Tronto, spokesman for the Italian fire department Luca Cari told Reuters. Helicopters would be sent up at first light to assess the damage, he said.
The mayor of Accumoli said a number of buildings had been badly damaged.
"Four people are under the rubble, but they are not showing any sign of life. Two parents and two children," Mayor Stefano Petrucci told RAI television.
RAI quoted police as saying two people were known to have died in the nearby village of Pescara del Tronto.
The mayor of the small town of Amatrice reported extensive damage.
"Half the town is gone," Mayor of Amatrice Sergio Pirozzi told RAI. "There are people under the rubble... There's been a landslide and a bridge might collapse."
Britain's foreign office released the following statement:
"An earthquake with a magnitude of 6.2 struck Central Italy during the early hours of 24 August. The earthquake was also felt in Rome. If you are in the affected area, you should follow the advice of the local authorities. If you are in Italy, Civil Protection have activated a hotline 800840840 for information. To learn more about what to do before, during, and after an earthquake visit the Protezione Civile website."
Meanwhile, Facebook has activated the safety check-in feature in order to let people alert friends and family that they are safe:
Devastation is widespread
REUTERS/Remo Casilli
The earthquake caused damage to towns in three regions - Umbria, Lazio and Marche.
The U.S. Geological Survey, which measured the quake at 6.2 magnitude, said it struck near the Umbrian city of Norcia, which has a picturesque historic centre and is a popular tourist site.
Mayor Nicola Alemanno said no deaths have been reported deaths in Norcia.
"The anti-seismic structures of the town have held. There is damage to the historic heritage and buildings, but we do not have any serious injuries," he told Rai.
Prime Minister Matteo Renzi's office said rescue teams were being sent to the worst-hit areas.
Italy's civil protection agency said the earthquake was "severe".
"It was so strong. It seemed the bed was walking across the room by itself with us on it," Lina Mercantini of Ceselli, Umbria, told Reuters.
USGS
Olga Urbani, in the nearby town of Scheggino, said: "Dear God it was awful. The walls creaked and all the books fell off the shelves."
Television stations showed images of rubble-strewn streets in a number of towns. The facades of some old stone buildings had collapsed, leaving the inside rooms exposed.
REUTERS/Remo Casilli
Residents of Rome, some 170 km (105 miles) from the epicentre, were woken by the quake, which rattled furniture and swayed lights in most of central Italy.
There were 17 reported aftershocks in the three hours following the initial quake, the strongest measuring 5.5, the Italian seismic office said. It measured the original quake at 6.0.
The last major earthquake to hit Italy struck the central city of L'Aquila in 2009, killing more than 300 people.