Details of the Tennessee native's passing were not provided.
"We are deeply saddened to share the news that we have lost a valued friend and colleague," the network's statement said.
"John was a brilliant, brave, and tireless journalist who guided viewers through many of the most significant events of the past half-century -- from the early days of the civil rights movement through the tragedy of 9/11. He covered five presidents and traveled to every corner of the world, always showing the empathy and compassion that helped set him apart.
"His kindness is remembered by all of us, and it built lasting bonds throughout our news division.
"Our love and support are with Nancy, Molly and Lee, Carter, Hope, and the entire Palmer family."
The veteran reporter and anchor worked for NBC from 1962 to 1990 and then again from 1994 until he retired in 2002. He was a television anchor and correspondent for Monitor Radio and Television from 1992-1994.
Among the many stories he's credited with breaking came on April 25, 1980, when he provided the first reports of the aborted rescue attempt of American hostages in Iran. He received the prestigious Merriman Memorial Award for Excellence in presidential news coverage for his work on that story.
He also anchored the first hours of NBC's coverage of the Challenger Space Shuttle tragedy on Jan. 28, 1986.
He covered the 1973 Arab-Israeli war, the Arab oil embargo, the war in Cyprus and the civil war in Angola.
He earned the Overseas Press Club Award and a National Emmy Award for his reporting on an African famine and an Emmy for his reporting on America's space program.
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