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.
More top news
Greeks have voted to reject the terms of an international bailout, putting it on the brink of a eurozone exit.
Amazon has promised its paid subscription customers a global shopping day with 'more deals than Black Friday.'
The former footballer said 'unbelievable' paranoia during his drug addiction led him to believe his Rolex watch was "listening" to him.