At least four people were killed as an earthquake measuring 6.1 on the Richter Scale struck central Italy early Wednesday, a government official said.At least four people died in the quake whose epicentre was determined at Rieti, around 170 km southwest of Rome, Xinhua news agency quoted central Amatrice town's mayor Sergio Pirozzi as saying.Strong tremors were felt in Italy's capital city of Rome, Xinhua news agency cited reports from Italy's National Institute of Geophysics and Vulcanology as showing.The US Geological Survey put the magnitude at 6.2 and said the quake was shallow.There were also reports of damage and collapses of buildings.People were trapped under the rubble of collapsed houses in the town of Amatrice."There are people under the rubble... There's been a landslide and a bridge might have collapsed," said 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.