BOLOGNA: Panicked people rushed into the streets when a powerful earthquake shook northern Italy early Sunday, killing three people and injuring at least 50, emergency services said.

Thousands of people in the area rushed into the streets after the quake, felt in the major towns of Bologna, Modena, Ferrara, Rovigo, Verona and Mantua in Northern Italy.

There was one report of a roof collapsing in Sermide, a small town between Bologna and Verona, and of a woman inside calling for help.

Firefighters said there were some “structural collapses” near the town of Bondeno, and the initial quake was followed by a fairly strong 5.1 magnitude aftershock.

“It's in the Bologna-Ferrara area. There’s been a bit of damage, some structures have come down with people in them,” a person at the Ferrara firefighter headquarters said over the phone.

The powerful earthquake lasting 20 seconds killed a man working the night-shift in a workshop, that collapsed in a plastic-producing factory, near the city of Ferrara on Sunday, rescuers said.

Two other people were reportedly killed in another region.

First television pictures taken after dawn showed serious damage to historic buildings and rural structures. Parts of a historic fortress in one town collapsed.

A series of strong aftershocks hit the area and local mayors ordered residents to stay out of their homes.

The temblor woke residents in Bologna shortly after 0200 GMT, shaking furniture and setting off car alarms, a Reuters reporter living there said. People exited on to their balconies, but soon went back to bed, he said.

The quake, which initially registered at magnitude 6.3, was centered 22 miles  north-northwest of Bologna in northern Italy at a relatively shallow depth of 6.3 miles , the USGS said.

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 Italy's financial capital, Milan.