A $332.2-million art collection has reportedly disappeared in China.

An art collection valued at €300 million ($332.2 million) has disappeared in China, according to reports by German outlets Süddeutsche Zeitung and Deutschlandfunk. The 342 missing works are by Renate Graf, Anselm Kiefer, and Markus Lüpertz, and come from the MAP collection, which belongs to Maria Chen-Tu, a German collector of Taiwanese ancestry.

The works had been on loan to a Chinese businessman who was to organize exhibitions at Chinese museums. The businessman, Ma Yue, has claimed he had been tasked with selling the collection and organizing exhibitions of the works for 10 years. However, his company Bell Art, based in Hamburg, began insolvency proceedings in January. Chen-Tu said she repeatedly requested the collection be returned to her, and alerted Beijing authorities in July.

According to the Deutschlandfunk report, as translated by The Art Newspaper, she told journalists:

The missing works include many early pieces by Lüpertz, a giant of postwar German art. At a Beijing press conference, the artist said: “The main problem is that we don’t know where the works are and we don’t know where they are stored and whether they have the necessary protection and care.”

In 2017, works by Kiefer (an artist best known for monumental works, often incorporating sheets of lead, wrestling with German identity post-World War II) belonging to Chen-Tu were featured in an exhibition at Beijing’s Central Academy of Fine Arts Museum. They became the subject of an international dispute after the artist and his dealers—the mega-galleries Gagosian, Thaddaeus Ropac, and White Cube—publicly criticized the show (which was co-organized by Bell Art) for being put together without the artist’s input or approbation.