The bizarre story was revealed during an email exchange between the victim, world deputy editor Anthony Massey, and 'Newsnight' presenter Jeremy Paxman, which was then circulated across the media.
In one email, Paxman asks Massey whether rumours Thompson had bit him were true. Massey replies: "It's absolutely true. I went up to his desk to talk about some story... before I could say a word he suddenly turned, snarled and sank his teeth into my left upper arm. It hurt. I pulled my arm out of his jaws, like a stick out of the jaws of a Labrador."
Giving further insight into the incident, which took place in 1988, Massey added: "I don't think it was personal. Something turned in his brain, and anyone standing there would have been bitten."
Massey also said he wanted to see Thompson disciplined at the time but the process "lost momentum" after he was sent on a foreign assignment for a month.
In his response, Paxman describes Thompson as "insane", adding, "bloody hell, if any of this came out, he'd be toast".
However, the BBC is downplaying the significance of the incident. A spokesman said: "It did happen but it was high-jinks and horseplay a lot earlier on in his career. Mark had forgotten about it but obviously Mr Massey hadn't."
This latest incident adds to an already torrid week for Thompson, who on Monday announced that a further 2,050, jobs were to be axed in an attempt to save £221m by 2008. This takes the total number of job losses at the BBC to 3,780.
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