SUFFOLK, Va. (AP) — Anthony J. Russo, a researcher who helped leak the Vietnam-era Pentagon Papers to the media and prompted wider public questioning of the war, has died, police said.

Russo, 71, died in his native Suffolk on Wednesday, police records technician Susan Hart said Sunday. The cause of death was not immediately made public.

The case that became known as the Pentagon Papers helped put the Vietnam War on trial.

It began when Daniel Ellsberg, a top military analyst disillusioned with American policy, decided to release a top-secret, 47-volume Defense Department study of the U.S. role in Indochina over three decades. Russo helped him reproduce and distribute copies of the study.

Ellsberg mourned Russo's death in a posting on his anti-war blog, calling him a courageous collaborator.