Dereck Chisora threw a table at Dillian Whyte during a heated news conference before their British heavyweight title bout in Manchester on Saturday.
The fighters sat with promoters and coaches between them on a long table when Chisora picked it up and threw it, prompting security to intervene.
During the event, Whyte told Chisora: "If I see you anywhere, I'm going to attack you - even after the fight."
Chisora, 32, said he reacted to what he felt was a threat against his life.
"Why should this guy threaten my life right now?" said Chisora, who has six defeats from 32 fights.
"Fight talk is fight talk. You can say anything you want about me. But one thing you cannot do is threaten a man's life. Saying you will see me after the fight. Then I get upset. I don't mind the trash talk."
Chisora has previously been involved in a controversial news conference when he brawled with David Haye in the aftermath of his 2012 defeat by Vitali Klitschko.
Both he and Whyte were initially scheduled to appear at separate news conferences because of the animosity between the two at previous media commitments.
During the news conference the fighters repeatedly exchanged insults and after the table was thrown, Whyte's trainer Mark Tibbs appeared to throw an object at Chisora.
Whyte, 28, is preparing to defend his British title for the first time and has suffered just one loss in 20 fights as a professional.
That defeat came against IBF world heavyweight champion Anthony Joshua, who headlines the card at Manchester Arena as the Briton makes his second defence against American Eric Molina.