Italian magistrates on Sunday opened an inquiry into the causes of a fire that gutted an aristocrat's library in the southern city of Cosenza on Saturday, killing three people living in an adjacent apartment and destroying ‘priceless’ works by the Renaissance philosopher Bernardino Telesio and letters to Galileo Galilei, the Telegraph quoted judicial sources as saying.
The leading Corriere della Sera newspaper described the private museum housing the collection of the Bilotti Ruggi D'aragona family as "the most important library in southern Italy." 
The owner of the library and well-known collector, Roberto Bilotti, said he had informed local authorities repeatedly about the risk posed by the three mentally handicapped squatters living in the apartment below the library where the fire started.
“This was a tragedy waiting to happen,” Bilotti said. “I had denounced the absurd situation with these neighbours to the public prosecutor’s office as long as eight years ago. These people had occupied a floor illegally. During the winter they lit fires to heat themselves… they needed help, but nobody took care of them.”
Books that went up in flames in the blaze included the first printed edition of Telesio’s great work 'De rerum natura iuxta propria principia' (On the Nature of Things according to their Own Principles).

source: Mena