Police described Monday a daring and rare heist where armed men struck in broad daylight and stole four major Impressionist works worth an estimated 180 million Swiss francs (163 million dollars)from a museum in Zurich, Switzerland, according to dpa. There were still visitors at the Emil Buehrle collection on Sunday afternoon when three masked men burst in. One held staff and visitors, who were in the entrance, at gunpoint on the ground while the other two removed the four paintings from the wall in a gallery on the ground floor. The alarm was triggered but they swiftly escaped in a white car, police told a press conference. A spokesman said these type of robberies normally took place at night. They took works by Claude Monet (Champ de Coquelicots Pres de V etheuil 1879), Edgar Degas (Ludovic Lepic et Ses Filles 1871), Vincent van Gogh (Branches de Marronier en Fleurs 1890), and Paul C ezanne (L'Enfant dans une Veste Rouge 1888/1890). They were among the works collected by the German industrialist Emil Buehrle (1890-1956). He moved to Zurich in 1924 and began collecting after buying Swiss Machine Tool Factory Oerlikon in 1936. The collection is described as one of the most important 20th century private collections of European art, with French Impressionism and Post-Impressionism at its heart. He really forged ahead with his collection in the few years before his death buying from dealers in New York, London, Paris and Zurich. The stolen works were on permanent display in the villa adjacent to Buehrle's former mansion as part of the Foundation set up by his family and opened to the public in 1960. As well as buying art he donated a new wing to Zurich's Kunsthaus in the 50's to which his family later transferred some of the collection. Sunday's theft came just four days after two Picassos worth an estimated 4 million dollars were stolen from an exhibition at Pf{ffikon not far from Zurich in central Switzerland.