The Boston Public Library is looking for two valuable artworks amid concerns that they may have been stolen as part of an inside job.

The Boston Herald reported Wednesday that an etching by Rembrandt and an engraving by Albrecht Durer were reported missing to police on April 29, approximately three weeks after a library supervisor noticed that they could not be found.

However, the Herald, citing a police source, reported that the prints could have been missing for up to a year before the report was filed. The source said it was also possible that the prints had been removed for display purposes and never put back.

Boston Public Library President Amy Ryan released a statement Tuesday saying that she hoped "that these two significant pieces have simply been misfiled."

The library is home to a collection of over 200,000 prints and drawings. Of those, approximately 30 are by Rembrandt, perhaps the greatest-ever Dutch artist. Another 105 are by Durer, a master of the German Renaissance.

The Durer work, titled “Adam and Eve,” is a 1504 engraving that measures about 8 inches by 11 inches. The Rembrandt, titled “Self-Portrait with Plumed Cap and Lowered Sabre,” is a 1634 etching that is about 5 inches by 6 inches. Police estimate the Durer piece to be worth approximately $600,000, with the Rembrandt worth between $20,000 and $30,000.

Boston recently marked the 25th anniversary of one of the most significant art thefts of modern times when thirteen works, including three Rembrandts, were stolen from the Isabella Stewart Gardner Museum. The FBI has linked the thefts to an organized crime ring operating in New England and the mid-Atlantic region during that time.

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