RIO DE JANEIRO -  Two pieces of artwork by Pablo Picasso and Brazil's Candido Portinari were stolen from the Sao Paulo Art Museum (MASP) where they were on exhibition.  "Portrait of Suzanne Bloch" by Picasso in 1904 and "O Lavrador de Cafe" ("The Coffee Farmer") by Portinari in 1939 were some of the most important pieces of the MASP's collection. Their value was not established since they had never been auctioned, but experts estimated the two paintings are worth at least 120 million U.S. dollars altogether.

According to police, it took only three minutes for thieves to steal the oil-on-canvas paintings, which were exhibited in two different rooms at the museum. The crime took place from 5:09 a.m. to 5:12 a.m. local time, although three security guards were at the spot at that time. Security cameras recorded the theft.

The museum also turned to the Foreign Ministry and Interpol for help.

The MASP's Administrative and Financial Superintendent Fernando Pinho said in a statement that no artwork had ever been stolen from the museum since it was founded 60 years ago.

Pinho added criminals have been targeting Brazil's museums lately. In February, artwork by Picasso, Henri Matisse, Salvador Dali and Claude Monet were taken from Chacara do Ceu Museum in Riode Janeiro.

Joao Portinari, son of the Brazilian painter, told local press that he believed the criminals may get in touch with him for negotiation. However, the police said the thieves probably had already found a buyer for the paintings, adding that the burglars tried to steal the works in October but failed.

Candido Portinari (December 29, 1903 - February 6, 1962) was one of the most important Brazilian painters and also a prominent and influential practitioner of the neo-realism style in painting.

Born of Italian immigrants in a coffee plantation near São Paulo.   Portinari studied at the Escola Nacional de Belas Artes (ENBA) in Rio de Janeiro. In 1928 he won a gold medal at the ENBA and a trip to Paris where he stayed until 1930, when he returned to Brazil.

His career coincided with and included collaboration with Oscar Niemeyer amongst others. Portinari's works can be found in galleries and settings in Brazil and abroad, ranging from the family chapel in his childhood home in Brodowski to his panels Guerra e Paz (War and Peace) in the United Nations building in New York. The range and sweep of his output is quite remarkable. It includes images of childhood, paintings depicting rural and urban labour, refugees fleeing the hardships of Brazil's rural north-east, treatments of the key events in the history of Brazil since the arrival of the Portuguese in 1500, portraits of members of his family and leading Brazilian intellectuals, illustrations for books, tiles decorating the Church of São Francisco at Pampulha, Belo Horizonte. There were a number of commemorative events in the centenary of his birth in 2003, including an exhibition of his work in London