A priceless collection of antique manuscripts and books that has been missing since Nazi troops looted it from the synagogue in Rome may be languishing in an abandoned Soviet military archive.

After leads from Italy to Germany, Poland, France, Ukraine and the US, researchers have secured an agreement with Russia to help to find the 7,000-volume library, which that dates back to the 16th century.

There is good reason to believe that the collection could be in a warehouse or other undocumented location, Dario Tedeschi, a lawyer who has been leading efforts on behalf of the Italian Government, said. Yesterday he described the decades-long hunt as “trying to unravel a historical mystery”.

This week Enrico Letta, an Italian undersecretary, signed an agreement with Ekaterina Genieva, director of the Library of Foreign Literature in Moscow, to pursue the Soviet trail in an effort to bring the collection home. Ms Genieva, an expert in tracing documents, was responsible for the return of the Vienna Jewish community’s collection. The research is being funded by Unicredit Private Banking with a donation of €30,000 (£20,400).

The collection, known as the Library of the Jewish Communities, includes illuminated manuscripts, books and Torahs and Bibles printed in the 16th and 17th century. There are works of philosophy, mathematics and astronomy, as well as religious works. A 1324 copy of a treatise on medicine by the Arabic scholar and philosopher Avicenna was one of the library’s gems.

Two collections were housed in the synagogue complex in Rome’s ancient ghetto. One group of books was taken in October 1943, around the time that more than 1,000 Jews were rounded up to be sent to Nazi camps such as Auschwitz. The other was taken that December.

Most of the volumes originally from the rabbinical college collection were later returned from Frankfurt, said Mr Tedeschi. But the Jewish Communities collection may have been taken to Raciborz, near Auschwitz, or to Hungen in the Rhineland. As Soviet troops pushed back the German forces, they may have taken possession of the collection.

Mr Tedeschi said that all the earlier searching had hinted at an eventual destination in Russia. “It’s a job of looking through archives,” he said.

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