Armed robbers stole a Zurich museum's four finest Impressionist masterpieces, worth US$164 million, in one of the world's biggest art raids, officials said on Monday.
The paintings by Paul Cezanne, Edgar Degas, Vincent van Gogh and Claude Monet were stolen from the Buehrle Foundation museum on Sunday evening, police said. The operation came only five days after another major art robbery in a nearby Swiss town.
Museum director Lukas Gloor said the stolen works are "the four finest in the museum's collection."
Three masked men entered the museum at around 4:30pm on Sunday and threatened staff with a pistol, police said in a statement.
The robbers loaded the paintings into a white car and drove off towards the suburb of Zollikon, southeast of Zurich.
"We're talking about the biggest ever robbery carried out in Switzerland, even Europe," Zurich police spokesman Mario Cortesi said.
The scale of the Zurich theft puts it in the premier league of art robberies over the past two decades.
Three Van Goghs worth US$182 million were stolen from a museum in Arnhem, the Netherlands in 1988, and 11 paintings went from the Gardner Museum in Boston in 1990 worth around US$145 million.
Little was known about the Buehrle robbers except that one of the men spoke German with a Slavic accent, police added.
The stolen paintings are: Monet's Poppies near Vetheuil (1879), Degas' Count Lepic and his Daughters (1871), van Gogh's Blossoming Chestnut Branch (1890) and Cezanne's Boy in a Red Waistcoat (1888).
Gloor said the paintings are so well known it would be impossible to sell them on the open market.
He did not exclude the possibility of a ransom demand, but said none had yet been received.
The museum is offering a reward of 100,000 Swiss francs (US$91,000) for information leading to the return of the paintings.
The Buehrle museum was founded by the German-born arms magnate Emil Buehrle.
Buehrle made his fortune with the Oerlikon-Buehrle munitions factory in Zurich, which sold arms to both sides in World War II.
He began collecting art in the 1930s but made most of his purchases of key Impressionist works in the post-war period. The museum opened in 1960 and holds more than 200 paintings.
The robbery came just days after thieves stole two paintings by Picasso worth US$4.5 million from a cultural center in the town of Pfaeffikon, some 30km southeast of Zurich.
The paintings, one showing a typically stark horse's head in blues, grays and whites and the other a still life of a glass and pitcher in red and green, belong to the Sprengel museum in Hanover, Germany.