At least 40 people including five children were killed in a large earthquake that hit the city of L'Aquila and neighbouring towns east of Rome early Monday, official sources said.
The 5.8 magnitude quake injured thousands and left many more trapped in the rubble.
''It's the worst tragedy since the start of the millennium,'' said Civil Protection chief Guido Bertolaso who is leading a huge rescue effort.
As Pope Benedict XVI prayed for the victims, especially the children, Premier Silvio Berlusconi cancelled a visit to Moscow to rush to the scene and several countries offered aid.
A cabinet meeting has been set for 19.00 ½ûÂþÌìÌà time (17:00 GMT).
The quake, which hit at 3:30 a.m. (01:30 GMT), had its epicentre just outside L'Aquila, a medieval city 100 km (60 miles) east of Rome.
It was felt as far away as Rome where people were woken up and some buildings shook.
At least 26 towns and villages were hit by the tremor in and around L'Aquila, the capital of the mountainous Abruzzo region.