Two Italian art historians say they believe they have uncovered dozens of sketches and paintings attributable to the Renaissance master Caravaggio.
The works are believed to date from Caravaggio’s time as a student in Milan, Italian media reports.
They were previously ascribed to the archive of painter Simone Peterzano, with whom he studied from aged 11.
But some experts have urged caution over the discovery, saying further verification is needed.
“I will wait to consult the complete research, but the drawings I’ve seen so far do not seem to me attributable to Caravaggio,” said Francesca Cappelletti, author of a book on the artist’s works.
Claudio Strinati, a prominent expert in 16th Century art, added that the claims were “completely absurd”.
The pictures, which form part of the Peterzano archive, range from sketches of the body to religious scenes.
Caravaggio – whose real name was Michelangelo Merisi – studied under Peterzano from 1584 to 1588, and no paintings from his youth are believed to have survived.
Previously, the paintings in question were attributed to Peterzano, but historians Maurizio Bernardelli Curuz and Adriana Conconi Fedrigolli say it was inevitable that some of the archive was Caravaggio’s work.
“Evidently no-one entertained the hypothesis” that this would be the case, Curuz said.
“It’s impossible that Caravaggio left no trace of his activity between 1584 and 1588 at the workshop of a painter who was famous and sought after at the time,” Mr Curuz was quoted as saying in Italian newspaper La Repubblica.
Alongside Ms Fedrigolli, the historian said his claims were based on two years’ research, investigating the 1,400 works in Peterzano’s archive, which are scattered between several churches in Milan and the Sforzesco Castle.
Speaking to Ansa, he added that the drawings demonstrated a “strong, quick but dirty hand” and showed “the faces, bodies and scenes the young Caravaggio would use in later years”.
Mr Curuz’s assertions about the cache are contained in a two-volume Kindle e-book, Young Caravaggio, published on Friday.
The artistic director of the Brescia Museum Foundation, Mr Curuz is no stranger to controversy.
In 2007, he branded Italy’s celebrated sculptor Antonio Canova “a cheat”.
Writing in Stile Arte magazine, he claimed Canova’s celebrated marble Venus Victrix – one of the biggest draws in Rome’s Galleria Borghese – had been partly produced by taking a plaster cast of a model’s breasts.
Two years earlier, he suggested that Renaissance painter Raphael had been secretly married to one of his models, but the relationship was covered up by his acolytes.
Both claims were met with scepticism from the art establishment – and scorn has also been poured on his pronouncements about Caravaggio.
A spokeswoman for Milan’s council, which maintains the Peterzano collection, said: “The drawings have always been there, and have never yet been attributed to Caravaggio.”
“We’ll be very happy to discover it’s true,” Elena Conenna told AFP news agency, “but it’s strange. They weren’t in a hidden place, they were accessible to all.”
Ms Conenna added she was not aware of a visit from the art historians in the past two years.
Claudio Strinati stressed that both historians had serious reputations, but added: “I consider this research to be interesting, but not important”.
Mr Strinati, who said he was familiar with the Peterzano collection, also described the drawings as “exercises of no artistic importance”.
Caravaggio had a violent and chaotic life, dying in mysterious circumstances at the age of 38.