Three people were killed and precious original manuscripts from the Renaissance era were destroyed after a fire tore through a historical building in the southern Italian city of Cosenza.

The victims have yet to be identified, but they are presumed to be two men and a woman who had squatted in the third-floor flat of a building in the center of the city, reported the ANSA news agency.

The fire broke out Friday afternoon on floor downstairs from where the writings of 16th-century scholar Bernardino Telesio were stored.

Cosenza-born Telesio is credited as one of the fathers of modern philosophy, moving on the science from the teachings of Aristotle.

His writings were seen as heretical and banned by the Catholic Church.

The first edition of his most important work, De Rerum Natura Iuxta Propria Principia (On the Nature of Things according to their Own Principles), was destroyed, along with other ancient manuscripts and parchments.

Firefighters are investigating the cause of the fire, but a leak from a gas canister used by the squatters, who had a history of mental health problems and several run-ins with the police, is one of the hypotheses, ANSA said.

"Today Cosenza is mourning three victims and has lost 500 years of history," Roberto Bilotti, the owner of the building and of the lost manuscripts, told ANSA.