VATICAN CITY (AP) — The United States is returning to the Vatican Library a letter written by Christopher Columbus in 1493 announcing his discovery of the New World that was stolen and replaced with a forgery.

It's the third such return in recent years after U.S. investigators determined that several authentic copies of the letter had been stolen from libraries across Europe and replaced with forgeries without library officials' knowledge.

U.S. Ambassador Callista Gingrich was presenting the letter Thursday to the chief Vatican archivist, Archbishop Jean-Louis Brugues, and the prefect of the library, Bishop Cesare Pasini.

The authentic letter had ended up in the possession of an Atlanta actuary who purchased it from a rare book dealer in New York in 2004, unaware it had been taken from the Vatican. His widow returned it.