On Monday’s show, Mr. O’Reilly played CBS News footage from 1982 that showed the violent protests and quoted other correspondents describing the scene. He also included an interview with Don Browne, a former NBC News bureau chief who oversaw coverage of Latin America, who said there were tanks on the streets of the Argentine capital. “It was a real country at war,” Mr. Browne said. “It was a very intense situation where people got hurt.”

Mr. O’Reilly’s efforts to refute the claims by Mother Jones and some former CBS News colleagues occurred both on the air and off on Monday. During a phone conversation, he told a reporter for The New York Times that there would be repercussions if he felt any of the reporter’s coverage was inappropriate. “I am coming after you with everything I have,” Mr. O’Reilly said. “You can take it as a threat.”

David Corn, one of the reporters on the Mother Jones piece, said that the issue was not whether Mr. O’Reilly had reported on a violent protest, but whether Mr. O’Reilly had reported from a war zone.

Former CBS News staff members said on Monday that Mr. O’Reilly’s account of his reporting on the protests in Argentina was flawed. Eric Engberg, a correspondent for CBS News for 27 years, reported on the same riot near the presidential palace in Buenos Aires in June 1982 as Mr. O’Reilly. He said in an interview that several CBS News camera crews were sent out to cover the angry crowds, who had heard that Argentina surrendered the disputed Falkland Islands to Britain. Though the crowd was unruly, Mr. Engberg said, the rest of the CBS News crew, which included veterans of war zones, thought “it was the chummiest riot anyone had ever covered.”

Mr. Corn said the video released by CBS News proved nothing. “The protest had a violent component that is not in doubt, our original piece reported that extensively,” Mr. Corn said. “The question is whether Bill O’Reilly was stating the truth when he repeatedly said that Argentine soldiers used real bullets and fired into the crowd of civilians and many were killed.”