Two treasured pieces of art — an etching by Rembrandt and an engraving by Albrecht Dürer — have gone missing from the Boston Public Library’s vaunted print collection, and investigators are probing whether the artwork was stolen through an inside job, the Herald has learned.

The library reported both pieces missing to police on April 29, after a BPL supervisor discovered they had gone missing on or around April 8, according to a police report obtained by the Herald.