A number of paintings by famous artists were stolen from an art gallery in Rotterdam, Netherlands, police say. The extent of the theft, which was committed overnight Monday, is still being determined by police and staff at the Kunsthal art gallery, Dutchnews.nl reported. The works are part of the \"Avant Gardes\" show that opened Oct. 7. Artists included in the exhibition are Karel Appel, Salvador Dali, Marcel Duchamp, Lucian Freud, Piet Mondrian, Pablo Picasso and Vincent van Gogh. \"Reading Girl\" by Henri Matisse is reportedly one of the paintings taken although police and gallery staff have not released a list of the stolen art. The paintings are from the Triton Foundation collection, which the gallery described as one that \"comprises representative works by the most important and influential artists of the late 19th century to the present day.\"