NORFOLK -- The man who masterminded what's been called the biggest espionage leak in U.S. Navy history has died.
John Anthony Walker, Jr. died Thursday at the Federal Correctional Institute in Butner, North Carolina, where he was serving a life sentence, according to the Federal Bureau of Prisons. He was 77.
"It couldn't have happened to a nicer guy," retired FBI agent Robert Hunter of Virginia Beach, who broke the case in 1985, told 13News Now when he heard the news.
Walker, who worked as a private detective in Norfolk, retired in 1976 as a chief warrant officer after 20 years in the Navy.
The Walker spy ring included his older brother, Arthur, and his son Michael. A Navy friend, Senior Chief Petty Officer Jerry Whitworth, was also involved.
John Walker was charged with dropping about 120 secret or confidential Navy documents in the rural Maryland countryside outside Washington. Authorities said he flashed a gun when agents approached but dropped it and surrendered.
Some of the documents came from the USS Nimitz, the nuclear-powered aircraft carrier where Michael was stationed.
Among subjects covered in the documents seized by the FBI in a wooded area of Montgomery County were deployment of Soviet navy vessels in the Mediterranean Sea and movements of Soviet merchant marine ships, a court affidavit said.
A letter among the confiscated documents said, "This delivery consists of material from 'S' and is similar to the previously supplied material. The quantity is limited, unfortunately, due to his operating schedule and the increased security prior to deployment. His ship departed in early March and they operated extensively just prior to deployment,'' according to the FBI.
The letter also solicited advice on ways to improve the photographing of documents.
During his Navy career, Walker had security clearance and access to classified information on the encryption of naval communications.
The Vietnam veteran was a communications specialist on aircraft carriers and nuclear missile submarines, taught radio procedures at a Navy school, and served on the staff of several major Navy commands, according to the Navy.
Walker apparently relied on the so-called "dead drop," a common spy technique where information is left in a secluded spot, the FBI said. At the area where the car had stopped, FBI agents recovered a large brown bag, partly filled with trash concealing a package wrapped in plastic containing the classified documents, the FBI said.
The FBI said a Soviet national assigned to the Soviet embassy in Washington was seen in the same area.
John Walker was to have been eligible for parole in 2015. No cause of death was released.
Arthur, who was convicted of espionage, died at the same N.C. prison on July 5 at the age of 79.