The huge blaze last September at the National Museum of Brazil (Museu Nacional) that caused the destruction of its building and many of its precious artefacts has been blamed on air conditioning units.

Police experts said that, due to the temperature being above 1,000 degrees Celsius where the blaze started, it is impossible to determine why the air conditioning units caught fire. They did note however that the units were receiving a stronger electrical current than they were designed to handle.

Federal police also stated that, aside from fire extinguishers, the museum lacked the recommended fire protection devices it should have had, including hoses, sufficient water sprinklers and fire doors.

"There were various pieces of evidence that allowed us to conclude that the air conditioning units were the primary cause of the fire," police expert Marco Antonio Zatta said.

The fire at the Museu Nacional reduced the building and much of its contents, including precious artefacts, to ashes.

The museum had held Latin America’s largest collection of historical artefacts and, after the fire, researchers retrieved a fraction of the museum’s collection, including skull fragments belonging to ‘Luzia’, the name given to a woman who lived 11,500 years ago.

Experts from Mexico's National Institute of Anthropology and History (INAH) are currently working alongside members of the Federal University of Rio de Janeiro to help rebuild the museum.