A 1.5 square metre chunk of wall collapsed at the ancient Pompeii archaeological site's House of the Citharede, officials said on Friday.
The wall is part of a non-frescoed cubicle adjacent to the atrium of another domus currently closed to the public, the House of the Terracotta Press.
The House of Citharede is named after a statue of Apollo Citharede that was found there and is now kept at a museum in Napes.
The area Friday's collapse is the last of two so-called 'Regions' that are set to be restored and safeguarded in the Great Pompeii Project, the Superintendency for the Archaeological Heritage of Naples and Pompeii said.
The Great Pompeii Project is a multi-million euro fund from the EU and Italian government to protect the area that was launched in 2013.
The ancient Roman city of Pompeii was preserved under ash from a volcanic eruption in 79 AD and rediscovered in the 18th century.
The 2,000-year-old site has become a symbol for decades of mismanagement of Italy’s cultural sites after a series of collapses that have sparked international outcry.
United nations culture body Unesco in 2013 threatened to scrap Pompeii from its prestigious World Heritage list if measures were not taken to save the ancient site.
