At least seven people have been killed and up to 50 others injured in a 6.0-magnitude earthquake near the northern Italian city of Bologna, according to the Italian news agency ANSA.
The strong quake struck at 4:04am local time (02:04 GMT) on Sunday in the country's industrial heartland while most people were sleeping, prompting thousands to run into the streets in panic.
Hospitals were evacuated as a precautionary measure.
Al Jazeera's Sabina Castelfranco, reporting from the worst affected town of Finale Emilia, said: "Scared people are out on the street and have refused to go back to their homes."
"There are apparently 13,000 people that have been displaced, and it is unclear whether there is going to be more victims found," she said.
"Authorities in the area have schools closed down until the situation stabilises," said Castelfranco.
"The new buildings are intact but mediaeval buildings, some of the bell towers and churches, have completely collapsed. You can see huge mountains of rubble in front of these beautiful buildings."
One person, believed to be a Moroccan man working a night shift in a polyester factory, died when he was hit by falling debris.
Two men, also working a night shift, were killed when part of a modern ceramics factory made of steel collapsed in the town of Sant'Agostino.
"He wasn't supposed to be there. He changed shifts with a friend who wanted to go to the beach," the mother of one of the victims told state television.
A woman was reported to have died after suffering a heart attack because of the quake, and several dozen people suffered minor injuries.
Rescue officials were checking reports that other people were buried under rubble and were preparing to house people
whose dwellings had been damaged or destroyed.
In the town of Finale Emilia, firefighters rescued a five-year-old girl who was trapped in the rubble of her house after a rapid series of phone calls between a local woman and emergency services.
"We were very afraid, all the village went out into the street after the first shock, after the second many took shelter in their cars, but fortunately the damage was fairly limited, above all affecting churches," Umberto Mazza, the mayor of Ostiglia, near Mantua, told the Italian news agency ANSA.
Heaps of rubble
First television footage showed half-collapsed houses with heaps of rubble on the roads and serious damage to historic buildings and churches in the province of Modena.
One badly damaged building was the 14th century Estes Castle in the town of San Felipe Sul Pan, near the quake's epicentre.
There were fears that one of the towers of the famous mediaeval castle, the town's biggest attraction, could collapse. The town's main church was also severely damaged.
The quake also shook the major cities and towns of Bologna, Modena, Ferrara, Rovigo, Verona and Mantua, though none reported serious damage.
A series of strong aftershocks hit the area, the strongest measuring 5.1, and local mayors ordered residents to stay out of doors.
The quake was centred 35km north-northwest of Bologna at a relatively shallow depth of 10km, the US Geological Survey said.
The epicentre of the quake, the strongest to hit Italy in three years, was in the plains near Modena in the Emilia-Romagna region of the Po River Valley, and the tremor was felt in nearby regions of Lombardy and Veneto.
The last major earthquake to hit Italy was a 6.3-magnitude quake in the central Italian city of L'Aquila in 2009, killing nearly 300 people.
In January, a 5.3-magnitude quake in northern Italy was felt in Genoa, Bologna, Turin and Milan.