The Bibliothèque Nationale de France (image via Wikipedia)

The National Library of France, which holds more than 14 million books, has seen a rash—OK, two—major thefts over the course of the past year, the New York Times reports.

First, approximately 20 three-centuries-old maps disappeared from the library’s Richelieu-Louvois branch (just “a 17^th-century mansion in the heart of Paris”) and then, more recently, 43 16^th-century engravings, together valued at $4.4 million, were cut from a book and wound up in the hands of a bookseller in Belgium.

Police investigators traced the stolen goods back to an employee at the same Richelieu-Louvois branch, where he was responsible for stocking and retrieving books and manuscripts from the archives. That employee, whose identity remains undisclosed, was detained earlier this month and is still being questioned.

Part of the problem seems to be security: the Richelieu-Louvois space is undergoing renovation, and while there are new measures in place—random searches at the exits, installation of surveillance cameras—the library’s labor union contends that “the building remains vulnerable.”

This event is not to be confused with the uproar surrounding a Dürer engraving (valued at $600,000) and Rembrandt sketch (valued at $30,000) that went “missing” from the Boston Public Library earlier this summer. In that case, both items were found misfiled, about 80 feet from where they belonged.