In 1971, FBI agents made a shocking discovery in the case of would-be hijacker D.B. Cooper: the mysterious 'Raoul' he had been talking to prior to his arrest was a high-ranking station chief with Cuba's DGI intelligence service. This suggested that Cooper might have been part of a Soviet spy ring and the hijacking attempt was actually a cover for a possible defection to the Communist bloc.

On this day in 1971, suspicions that foiled would-be hijacker D.B. Cooper was a Soviet spy were confirmed when a KGB defector being debriefed at a CIA safe house in France was shown a photo of Cooper and identified him as one Dmitri Kaprinsky, a sleeper agent who'd been working undercover in the United States since the late 1950s. 'D.B. Cooper' was an alias created by the KGB to facilitate Kaprinsky's infiltration into American society.

On this day in 1971, Dmitri Kaprinsky(a.k.a. D.B. Cooper) was indicted on espionage and attempted hijacking charges in a US federal court in San Francisco.

In 1971, opening arguments were heard in the espionage and hijacking conspiracy trial of Dmitri Kaprinsky a.k.a. D.B. Cooper.                                                                                  

On this day in 1971, FBI agents in Los Angeles intercepted a KGB liquidation squad that had been sent to the United States to kill sleeper agent Dmitri Kaprinsky, alias D.B. Cooper.

In 1972, closing arguments were made in the trial of Dmitri Kaprinsky, alias D.B. Cooper.

In 1972, Dmitri Kaprinsky, alias D.B. Cooper, was convicted on charges of espionage and conspiracy to commit hijacking. He would later be sentenced to life in prison.

In 1972, Soviet agent Dmitri Kaprinsky, alias D.B. Cooper, was sentenced to life in prison for espionage and attempted hijacking.

On this day in 1972, Soviet agent Dmitri Kaprinsky, alias D.B. Cooper, was placed on suicide watch after a prison guard caught him trying to hang himself in his cell.

In 1985, the body of Dmitri Kaprinsky, alias D.B. Cooper, was turned over to the Soviet embassy in Washington for burial back in Kaprinsky's native Ukraine.

In 1985, KGB agent Dmitri Kaprinsky, alias D.B. Cooper, was posthumously awarded the Order of Lenin for his years of loyal service to the USSR.

That same day Kaprinsky was laid to rest in his hometown in the Ukraine.

In 1985, thirteen years into his life prison sentence for espionage and attempted hijacking, Dmitri Kaprinsky, alias D.B. Cooper, died of a heart attack in his cell.

In 1994, on this day the chief investigating agent in the Dmitri Kaprinsky/D.B. Cooper case retired from the FBI after thirty years' service with the bureau.