A powerful 6.1-magnitude earthquake struck central Italy early Wednesday, with strong tremors felt in Italy's capital Rome, according to reports from Italy's National Institute of Geophysics and Vulcanology.

Rome is some 170 km southwest of the epicenter of the quake near the central city of Rieti.

The United States Geological Survey put the magnitude at 6.2 and said the quake was shallow.

The quake occurred at 03:36 a.m. local time (0136 GMT). So far, there have been reports of damage and collapses of buildings, but no reports of casualties.

There are people trapped under the rubble of collapsed houses in the central town of Amatrice, RAI state television reported.

"There are people under the rubble... There's been a landslide and a bridge might have collapsed," said the town's mayor Sergio Pirozzi.

"The roads in and out of town are cut off. Half the town is gone."

Prime Minister Matteo Renzi's spokesman said on Twitter that the government was in touch with the country's civil protection agency.