ROME -- Caravaggio was notorious for his brawling, so it might be fitting that a claim by two Italian art historians that they discovered as many as 100 drawings by the painter in his boyhood has sparked an art world uproar.

The researchers say they found dozens of early drawings by Caravaggio in the collection of master Milanese artist Simone Peterzano, the painter's teacher from 1584 to 1588. Many experts have responded with skepticism to the startling claim: Over the centuries, art historians have never definitively attributed any drawings to Caravaggio, who shook up 16th-century art by using models from the lower walks of life for religious scenes and dramatically counterpointing light and dark.

On Friday, the curator of the drawings collection at Milan's Sforzesco Castle, where the collection of 1,500 painting generally attributed to Peterzano is kept, challenged the seriousness of the researchers' methods and contended that the pair had never set foot in the room to scrutinize the works....