This undated image made available by the University of Durham on Friday shows the frontispiece of a priceless edition of Shakespeare's works stolen 10 years ago and was recovered after a man took the book into a U.S. library and asked to have it authenticated.

Washington ? A stolen volume of William Shakespeare’s collected plays, published in 1623 and worth about $2.5 million, has been recovered following antiquarian detective-work by experts at the Folger Shakespeare Library in Washington – where a mysterious man presented the precious book several weeks ago.

Police in Durham, in northeast England, on Friday were questioning a 51-year-old man in connection with the case after an international search for suspects. The book known as Shakespeare’s First Folio – the first published collection of the bard’s plays seven years after his death – was stolen from Durham University in 1998.

Shakespeare scholars and rare-book lovers on both sides of the Atlantic hailed the news.

The break in the case came June 16 when a man with a British accent arrived without an appointment at the Folger library on Capitol Hill. He had an old book and a strange story to go with it: He said the work was from a family library in Cuba, and he was representing the family. He wanted the experts at Folger to tell him if it was a genuine and important volume by Shakespeare.

“From time to time people have asked us to help them to figure out what a book might be,” said Garland Scott, head of external relations for the library, which has one of the world’s largest Shakespeare collections, including 79 First Folios. “On the other hand, usually those people have called or e-mailed beforehand. It’s a little unusual to just show up.”

Librarian Richard Kuhta saw the man and examined the book. “It was clear to Richard immediately that this is something important,” Scott said.

Kuhta asked the man if the library could hold on to the volume for further study, and the man agreed. “Alarm bells” were going off in the minds of the library’s staff, Scott said.

The man returned a few days later, and Kuhta asked if the library could keep the volume a little longer to consult with an outside expert. Further study convinced the Folger staff that this indeed was the stolen Durham First Folio.

The library contacted the FBI, and police in Durham were notified by the British Embassy in Washington.

Officers of the Durham Constabulary arrested the suspect on suspicion of theft Thursday and he was still being questioned late Friday, local time. A police spokesman said he also could be charged with handling stolen property.