AKIPRESS.COM - Forensic experts are waiting to enter Brazil's oldest scientific museum amid fears a fire destroyed most of its 20 million artefacts, Sky News reports.

Flames engulfed the 200-year-old national museum in Rio de Janeiro on Sunday.

Protesters clashed with police after the blaze following complaints that years of government neglect had contributed to its destruction.

The museum held Latin America's largest collection of historical and scientific artefacts, with one official telling a Brazilian news outlet that as much as 90% may have been destroyed.

Firefighters initially struggled to contain the flames because the hydrants closest to the museum did not work.

The cause of the blaze is not yet known.

Brazil's culture minister Sergio Leitao told local media that the fire was likely caused by either an electrical short-circuit or a homemade paper hot-air balloon that may have landed on the roof.

The museum, whose main building was once a 19th century royal palace, had contained a skull called Luzia that was among the oldest fossils ever found in the Americas.

It held an Egyptian mummy and the largest meteorite ever discovered in Brazil - one of the few objects that officials could confirm had survived.