Archaeologists have discovered new evidence pointing to the reoccupation of Pompeii after the 79 AD eruption of Mt Vesuvius that left the city in ruins, the directors of the famous site have said.

Despite the massive destruction of Pompeii, an ancient Roman city home to more than 20,000 people before the eruption, some survivors who could not afford to start a new life elsewhere are believed to have returned to live in the devastated area.

Archaeologists found evidence of Pompeii's reoccupation after the 79 AD eruption of Mt Vesuvius. Photo / Pompeii Archaeological Park, AFP

Archaeologists believe they were joined by others looking for a place to settle and hoping to find valuable items left by Pompeii’s earlier residents in the rubble.

“Judging by the archaeological data, it must have been an informal settlement where people lived in precarious conditions, without the infrastructure and services typical of a Roman city,” before the area was completely abandoned in the fifth century, they said.

While some life returned to the upper floors of the old houses, the former ground floors were converted into cellars with ovens and mills.

“Thanks to the new excavations, the picture is now clearer: post-79 Pompeii reemerges, more than a city, a precarious and grey agglomeration, a kind of camp, a favela among the still-recognisable ruins of the Pompeii that once was,” said Gabriel Zuchtriegel, director of the site.

Survivors and newcomers lived in precarious conditions, converting ground floors into cellars with ovens and mills. Photo / Pompeii Archaeological Park, AFP

Evidence that the site was reoccupied had been detected in the past, but in the rush to access Pompeii’s colourful frescoes and still-intact homes, “the faint traces of the site’s reoccupation were literally removed and often swept away without any documentation”.

“The momentous episode of the city’s destruction in 79 AD has monopolised the memory,” said Zuchtriegel.

Archaeologists estimate that 15% to 20% of Pompeii’s population died in the eruption, mostly from thermal shock as a giant cloud of gases and ash covered the city.

Volcanic ash then buried the city, perfectly preserving the homes, public buildings, objects and even the people until its discovery in the late 16th century.

A Unesco World Heritage Site, Pompeii is Italy’s second most-visited tourist spot after the Colosseum in Rome, with about 4.17 million visitors last year.

It covers a total area of approximately 22ha, a third of which is still buried under ash.

- Agence France-Presse