RAVANUSA, ITALY, DECEMBER 13

Rescuers were pulling out bodies on Monday from the rubble of houses destroyed by a suspected gas explosion on Saturday in the Sicilian town of Ravanusa, with the national fire service confirming at least seven people had died in the incident.

Sniffer dogs found four bodies in the early hours of the morning, including a nurse that was nine-months pregnant, and firefighters and men from the Civil Protection Department were extracting them from the wreckage, according to a Reuters witness.

Three bodies were found in the night between Saturday and Sunday and two people are still missing, a spokesman for the national fire service said on RAI NEW24 television.

In the explosion late on Saturday, four houses collapsed and another three were damaged, authorities said, adding the blast was likely triggered by a gas leak from the town's pipes, although an investigation was underway to ascertain the cause.

Ravanusa is a town of about 11,000 people near the southwestern Sicilian city of Agrigento, which is famous for its Greek temples.