Firefighters found the bodies of a married couple in their 80s and a male relative, 54, in the rubble after the buildings fell Monday night, and were searching for another woman, 74, the Italian news agency ANSA reported Tuesday.
Seven people were injured, including three children, ANSA said.
No cause was given, but residents said they heard strange noises in the buildings, and observed cracks in the walls.
"We called the fire brigade, who immediately had us evacuate," said Giuseppina Ferrara. "A few minutes later it all came down."