Officials at Brazil's top modern art museum where two prized paintings were stolen this week have admitted its collection is uninsured.
The paintings were highlights of the museum's collection
The Sao Paulo Museum of Art also said there were major failures in the security system.
Officials said no alarm was operating when the works by Pablo Picasso and the influential Brazilian artist, Candido Portinari, were stolen.
Burglars entered the building before dawn in a raid lasting three minutes.
Officials also said there were no movement sensors in the galleries and that security cameras only produced unclear images of the raid because they had no infrared capability.
The president of the museum, Julio Neves, has admitted shortcomings in security at the institution and vowed to upgrade.
"We don't have the resources for it. Now, we are going to update. We can improve some equipment," he told Reuters news agency.
Portinari was an important Brazilian painter
Correspondents say the lack of insurance for the museum's entire collection, which includes works by Renoir, Van Gogh and Modigliani, has shocked the art world.
Pablo Picasso's Portrait of Suzanne Bloch, and The Coffee Worker by Brazil's Candido Portinari, were stolen in Thursday's raid at Brazil's premier modern art museum.
The Portrait of Suzanne Bloch, painted in 1904, is estimated to be worth about $50m (£25m).
The Coffee Worker (O Lavrador de Cafe) was painted in 1939 and has been valued at around $5m (£2.5m).
The museum will remain closed while investigations are carried out.
Lead police investigator Marcos Gomes de Moura said he suspected it was a made-to-order theft.
"Everything indicates [the thieves] were sent to do it by some crazy, wealthy art lover for his own collection," he told the Associated Press news agency.
Thieves have targeted Brazil's museums before. In February 2006, a five-man gang stole works by Salvador Dali, Henri Matisse, Picasso and Claude Monet from a Rio de Janeiro museum.