The UNESCO World Heritage site came under scrutiny in early November when one of its archaeological treasures, the "House of the Gladiators," crumbled, CNN reported Friday.
Recent heavy rainfall has reduced the walls of four more buildings to rubble, the organization charged with the site's upkeep said.
Considered one of the most important archaeological sites in Italy, Pompeii was all but destroyed when a volcanic eruption from nearby Mount Vesuvius buried the city in ash, which preserved the remains to an astonishing degree.
Critics say the site has been allowed to deteriorate through neglect and mismanagement.
"The current state of conservation in Pompeii is mediocre," said Pietro Giovanni Guzzo, former superintendent and archaeologist at Pompeii.
Guzzo retired in August 2009 after 15 years in the post.
"There has been no maintenance for decades," said Alessandra Mottola Molfino, president of Italia Nostra, Italy's oldest heritage charity.
Mottola Molfino places the blame on the Italian government.
Five days after the collapse of the House of the Gladiators, the president of the Chamber of Deputies Commission for Culture, Valentina Aprea, denied allegations of neglect by the government.
"The exceptional nature of the site of Pompeii has never been neglected by an Italian government," she said.
The government has put emergency measures in place at Pompeii, giving the supervising organization stronger powers to protect the site as well as making plans to increase the number of archaeologists and skilled workers there, a government statement said.