A 47-year-old mystery finally may be resolved.

Grand Rapids-based publisher Principia Media announced yesterday it has released a book that allegedly reveals the real identity of “D.B. Cooper,” the infamous skyjacker who in 1971 demanded a $200,000 ransom on board a flight from Portland, Oregon to Seattle’s Sea-Tac airport, before jumping 10,000 feet to his escape.

The book, “D.B. Cooper & Me: A Criminal, A Spy, My Best Friend,” is by Carl Laurin, an alleged friend of the skyjacker, and details an investigation into Cooper’s identity.

Laurin claims that Cooper was the late "military paratrooper, daredevil and intelligence operative" Walter R. Reca, Principia Media said.

Reca, of Oscoda, Michigan, was born in 1933 and died in 2014, said Julie Hurley, a spokesperson for Principia Media. 

Principia Media said it has a set of supporting "evidence": the flight path and landing zone; "witness" testimony from an individual Laurin claims spoke with Cooper within an hour of his jump; and documentation of how the $200,000 was spent.

Laurin also claims to have three hours of audio recording from 2008 between himself and the skyjacker.

The publisher hosted a press conference today at the Amway Grand Plaza in Grand Rapids to discuss the book.

The author will be signing copies of the book at 5:30 p.m. today at Schuler Books in Grand Rapids, at 2660 28th St. SE.