At least 200 of 1,500 artworks discovered in Germany that were confiscated by the Nazis in the 1930s and 1940 are the subject of international warrants, news magazine Focus reports.
The collection is reported to include artworks by master painters such as Picasso, Chagall and Matisse with an estimated value of about one billion euros (£846m).
The works are being held in a secure warehouse in Munich at present while art historians attempt to determine the origin and value of the images.
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