(JTA) — A Monet painting was found in the suitcase that German art collector Cornelius Gurlitt, whose uncovered trove of Nazi-looted artworks shocked the world, took to the hospital when he died.

Gurlitt, who before his death had agreed to return the mostly early 20th-century paintings to heirs of the rightful owners, died in early May, several months after heart bypass surgery.

The executor of Gurlitt’s estate last week discovered the French Impressionist artwork in a suitcase handed over to him by the hospital, according to reports.

The painting, believed to be painted around 1864 and similar to the French artist’s “View of Sainte-Adresse,” will be researched to determine whether it was stolen by the Nazis, as were many other works in Gurlitt’s collection.

Some 1,400 works were confiscated from Gurlitt’s 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. The investigation is now closed due to his death.

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 such great painters as Picasso, Dürer, Renoir, Toulouse-Lautrec, Beckmann and Matisse.

A month before his death, Gurlitt signed an agreement with the state of Bavaria and the German federal government according to which the provenance of all works would be researched, paving the way for the return of the paintings to heirs of the rightful owners.

He bequeathed the trove to the Bern Art Museum in Switzerland.