The collapse Saturday at one of Italy's main tourist attractions was a source of embarrassment for the government and the country. President Giorgio Napolitano said it was a "disgrace for Italy" and demanded an explanation.
Culture Minister Sandro Bondi, who went to Pompeii to survey the damage on Sunday, warned that other buildings could also fall, according to Italian news agencies.
Given the number of buildings that need restoration, further damage is virtually "inevitable," said Daniela Leone, a spokeswoman for Pompeii's archaeological superintendence.
"This is a vast area that requires maintenance, resources," she said.
The house that collapsed on Saturday was used by gladiators to train before going to fight in a nearby amphitheater, as well as by other athletes. It was also a storehouse for weapons and armor.
It was believed to have been built not long before Pompeii was destroyed in A.D. 79 by an eruption of Mount Vesuvius, which killed thousands of people and buried the city in 20 feet (six meters) of volcanic ash.
The house was also partially destroyed during World War II, and the roof and some of the walls had been rebuilt.
Bondi suggested that water infiltration following heavy rains and the heavy roof added during the postwar restoration were to blame.
However, he said some frescoes on the lower parts of the walls may be saved, and urged more government funds for Pompeii.