The magnitude 6.0 quake struck near Bologna at 2am local time on Sunday morning.

Two people were killed when a ceramics factory caved in, and another died in the collapse of a factory.

Rescue teams are now searching the area after reports that survivors are buried under rubble.

The towns of Bologna, Modena, Ferrara, Rovigo, Verona and Mantua were all affected.

Thousands of people rushed into the streets when the quake hit, and residents were warned by officials to stay out of their homes as heavy aftershocks of up to 5.1 shook the area.

Local Modena resident Matthew Hatton told Sky News that he was in a bar when the owner suddenly told everyone to get out.

He said: “There were a few people crying. It was quite a strange experience. There were car alarms going off – that kind of thing. For four or five seconds it was really quite a strong one.”

News agency Reuters reported severe damage to historic buildings in San Felice Sul Panaro, close to where the earthquake erupted.

Its 14th century Estense Castle and main church were both heavily damaged, while one of the towers of its renowned medieval castle was thought to be in danger of collapsing.

The last time Italy was hit by a major earthquake was in 2009, when a 6.3 magnitude quake struck L’Aquila, the capital of Abruzzo in the centre of the nation, killing 308 people and damaging between 3,000 and 11,000 buildings.

The devastation left 40,000 people homeless.

As international leaders gathered in Chicago for a Nato summit focused strongly on the future of Afghanistan, a senior official disclosed there could be a continued fighting role for UK forces.

David Cameron has always insisted all British involvement in combat operations will end in 2014 as Afghan forces take responsibility for their own security.

He has said any future British commitment would be focused on training and mentoring the Afghans – such as the establishment of an officer training academy, dubbed “Sandhurst in the sand”.

However a senior British official indicated the UK could retain a small presence – most probably special forces – to counter any attempt by al Qaida to re-establish a foothold in the country after most international troops have left.

“As we’ve said previously, British forces will not remain in a combat role in Afghanistan beyond 2014,” the official said. “The majority of forces that remain in Afghanistan will be in a training and mentoring role, for example at the Afghan Officer National Training Academy. But I wouldn’t rule out a small number of forces playing a counter terrorism role if needed. This would be in keeping with how we are working to protect ourselves from the counter terrorism threat emanating from other parts of the world, such as the Arabian Peninsula.”

Ministers have always argued that the ultimate rationale for Britain’s involvement in Afghanistan was to protect the UK from terrorism in the wake of the 9/11 attacks launched from training camps in the country.

Al Qaeda has since shifted the focus of its activities to countries such as Yemen and Somalia, but the absence of international troops in large numbers could tempt it to make a return to Afghanistan.

Much of the discussion in Chicago will centre on how the Afghans manage after 2014. The gathering will also consider the future role of the alliance itself as economic austerity forces governments to squeeze defence spending.

Cameron will argue forcefully that reduced spending on armed forces must not mean any lowering of Nato’s ambition, and that it must continue to be prepared to tackle threats beyond its borders. He will reiterate the importance of Europe pulling its weight in the alliance – genuinely partnering the US rather than subcontracting its security to Washington.