(JTA) — An anonymous donor has given more than $1 million to help a Swiss museum take care of a bequest of hundreds of artworks, which may include Nazi-looted art.

The donation will help the Kunstmuseum Bern, or Bern Museum of Fine Arts, to house the collection of the late German art collector Cornelius Gurlitt of about 1,000 artworks, the French news agency AFP reported Thursday. The donor asked to remain anonymous.

The museum on Monday formally agreed to accept the collection, but said that it would work with German officials to ensure that all looted art in the collection is returned to its owners or their heirs. Gurlitt named the museum his sole heir before his death in May.

The collection reportedly is worth about $1.26 billion. The museum said it had no prior relationship with Gurlitt.

A German task force will continue to investigate the provenance of the artworks to determine which pieces were looted and to discover their rightful owners. Pieces for which no owners can be identified will be displayed in Germany in order to try to find the owners or heirs, according to the museum.

Some 1,400 works were confiscated from Gurlitt’s Munich home in 2012 in the course of an investigation for tax evasion. Other works were subsequently found in Gurlitt’s second home in Salzburg, Austria.

Gurlitt’s father, Hildebrand, was an art dealer on assignment to the Nazis. When Hildebrand Gurlitt died in 1956, his son inherited the collection, which includes works by Picasso, Durer, Renoir, Toulouse-Lautrec, Beckmann and Matisse.

In April, Gurlitt signed an agreement with the state of Bavaria and the German federal government in which the provenance of all works would be researched, paving the way for the return of the paintings to the heirs of the rightful owners.

The work of the task force in searching for possible rightful owners continued after Gurlitt’s death.

The museum is set to publish this week a list of all the artworks in the collection, the first time such a comprehensive list will be available, according to AFP.