On May 28, 1982, Joseph Billie Gwin, then 28, took four people hostage at the KOOL-TV station in Phoenix, Arizona. He eventually surrendered but not until news anchor Bill Close read Gwin's 20-minute statement on live television with a gun pointed at his stomach under the table. Gwin watched a portable TV to make sure they were on air.
From a 1982 New York Times report on the incident:
The message needed to be broadcast "to prevent World War III," the police quoted Mr. Gwin as saying. In it were other predictions, such as that that Senator Edward M. Kennedy, Democrat of Massachusetts, would become President, and that on July 4, 1984, atomic bombs would flatten cities in Pennsylvania, Arkansas, Nebraska, Idaho and New Mexico.
Station officials interrupted network programs at 9:30 P.M. to broadcast Mr. Gwin's statement. The statement called on Johnny Cash, the country-western singer, to notify Queen Elizabeth II to evacuate London before the Argentines could drop an atomic bomb on the city.[…]
Mr. Close, 61, took the gun after reading the statement and put the weapon on the table. He waved the police away and briefly shook the intruder's hand. Later, he said, "I feel that I was in control most of the time, even when he fired a shot into the ceiling. I think I'll go home and kiss my wife."
According to Wikipedia, Gwin was "charged with kidnapping, assault and burglary, and was later declared insane. Gwin was released from prison in 2005."
(Thanks, UPSO!)