Churches and a gallery in Rome housing works by Caravaggio will stay open overnight to mark the 400th anniversary of the Italian painter's death.

Three churches in the centre of the city — Santa Maria del Popolo, Sant'Agostino and San Luigi dei Francesi — will hold all-nighters.

Visitors can also enter for free from dusk Saturday until Sunday morning at the Borghese Gallery, which houses such masterpieces as David with the Head of Goliath and Boy with a Basket of Fruit.

The artist is known for his trademark technique called "chiaroscuro" which uses dramatic dark-and-light contrasts.

New work uncovered: Vatican newspaper

The all-night openings coincide with a report in the Vatican newspaper Saturday declaring that a new Caravaggio painting may have been found in Rome.The L'Osservatore Romano reported Saturday that a painting titled The Martyrdom of St. Lawrence and belonging to the Jesuits in Rome could be a newly discovered Caravaggio work. (Gregorio Borgia/Associated Press)

The front-page story in L'Osservatore Romano concerns The Martyrdom of St. Lawrence, which belongs to the Jesuits in Rome, the paper said.

An image of the work was published above the headline, showing a semi-naked young man, his mouth open in desperation, one arm stretched out as he leans over amid flames.

"It is up to further analyses and ... a stylistic and critical examination to provide us with answers," L'Osservatore Romano said.

Caravaggio died in the Tuscan coast town of Porto Ercole in 1610. At 39, he had been hugely influential and famous, but had also led a dissolute life of street brawls and alcohol.

Investigators recently unearthed what they say are the bones of the artist at a church in the town.

Part of a skull, two jaw pieces and a femur were taken from a small church in the town and examined for a year by Italian researchers, who pronounced in mid-June they were 85 per cent certain the bones belonged to the artist.

They are now on display in Porto Ercole.