Gas leak likely cause of explosion in Sicilian town.

Two people are dead and seven still missing after a four-storey building collapsed in the town of Ravanusa, in the sout-west Agrigento area of Sicily, on Saturday night.

Rescue efforts continue as two women, one of whom is 80 years old, were extracted alive from the rubble in the early hours of Sunday morning.

The two dead are a man and a woman, according to firefighters at the scene.

State broadcaster RAI News reported earlier that those unaccounted for included a pregnant woman. Initial reports that the people missing included two children were not correct, authorities said.

The cause of the explosion is believed to be accidental, probably a gas leak, according to emergency services.

One theory is that a large amount of gas accumulated in the ground under the building, reports Italian news agency ANSA.

The explosion damaged several other neighbouring buildings, with local residents describing the scene to Italian newspaper Corriere della Sera as resembling a "war zone".

There are reportedly 50 firefighters working at the site, along with dozens of civil protection volunteers and police officers.

This is a developing story.