Previously unknown artworks by masters including Marc Chagall, Otto Dix, Max Liebermann and Henri Matisse are among those found inside a flat in Munich.
Prosecutors said the issue of ownership was still to be clarified. The total value has been estimated at about €1billion (£846 million).
Other artists whose works were found include Pablo Picasso and Henri de Toulouse-Lautrec, as well as Canaletto and Gustave Courbet.
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