Two structures have collapsed following heavy rain in the ancient Roman city of Pompeii, one the world's most renowned archeological parks.
A few stones fell late on Saturday from the Arch of Venus, a site that was already sealed off from visitors, Italian conservation authorities said.
More serious damage was discovered on Sunday morning was the crumbling of a 3.5-metre section of a wall at the Necropolis of Porta Nocera.
Normally open to the public, the area was immediately sealed off.
Culture Minister Dario Franceschini has called a crisis meeting for Tuesday to assess the damage.
Since 2010, more than a dozen buildings at the UNESCO World Heritage site have crumbled, renewing international concern about the failure of Italy's cash-strapped institutions to look after the country's cultural heritage.
In Pompeii, investigations have revealed that past maintenance and restoration work was undermined by corrupt officials and infiltration by the local mafia, the Naples-based Camorra.
The European Union has joined Italian efforts to rectify the situation, funding most of a 105 million euros ($A161.89 million) restoration scheme. Only last week, authorities announced the completion of work on the first section of the project.
Once a prosperous Roman city, Pompeii was destroyed in 79 AD, along with nearby Hercolaneum, by an eruption of Mount Vesuvius that killed thousands of people and buried them in six metres of volcanic ash.
