Investigators dedicated to uncovering the true identity of infamous 1971 airplane hijacker DB Cooper claim they now have the final pieces of evidence that proves it is the man they have long pinned it on.

The notorious hijacker, who is one of the 20th century's most compelling masterminds, hijacked a Boeing 727 at Seattle-Tacoma airport in 1971 and held its crew and passengers hostage with a bomb.

Once his demand of $200,000 cash - the equivalent of $1.2 million today - was reached and transferred onto the plane, he had the crew take off before he parachuted out over the dense Pacific Northwest woods and disappeared.

The hijacker was dubbed DB Cooper by the FBI.