The tragedy that is Greece. A conflict that has exploded across our TV screens, pitting brother against brother. And that's just in the Newsnight studio.

Jeremy Paxman is famed for exposing the evasions and obfuscation of his guests. But last night, seemingly frustrated by the absence of someone to interrogate, he chose to turn on his own colleague, Paul Mason.

The bizarre exchange began as Mason began to sign off a package he had produced on the day's unrest in Athens. "There's sporadic rioting going on", said Mason, "and not a single politician can leave their secure accommodation". Describing the situation as "a little bit chaotic", Newsnight's economics editor explained that the austerity package had nevertheless been passed in the face of what he termed "viscerally felt anger".

At which point the BBC's grand inquisitor pounced. "Oh come on Paul, it was hardly the entire population of Athens on the streets was it, and certainly not the entire population of Greece". Mason, who had spent the day dodging tear gas and riot police, appeared momentarily stunned, his face set in an expression that made it look like he'd swallowed an Athenian wasp.

"But if people are, as you say, losing faith in such numbers", followed up Paxman pointedly, "where does that lead?"

For a moment the nation's Newsnight viewers held our collective breaths in the hope it might lead to Mason storming off live on air. But showing a level of restraint markedly absent from the streets of the Greek capital, he confined himself to a gritted, "There are a lot of people out Jeremy".

A clip of a Greek commentator helpfully comparing the situation in his country to 1930's Germany momentarily cut across the BBC's own domestic strife, but when we returned Mason was shaking his head and had a strange grin on his face. The rest of the two-way passed offpeacefully until in the final exchange, when Newsnight's economics editor threw down his own challenge over who was responsible for the collapse of the Eurozone; "the people who run the Eurozone, you tell me Jeremy who that is, who we ask the question of". Jeremy didn't.

Badinage between colleagues is all part of the Newsnight brand. But few journalists I've spoken to can ever recall an anchor directly challenging a colleague over his description of events on the ground. One broadcast correspondent working for a different outlet seemed perplexed at Paxman's challenge to Mason; "We've got guys out in Athens and from what we had coming back yesterday it certainly looked like it was getting a bit tasty".

BBC colleagues denied there was any "history" between the two men. "Paul likes to wear his heart on his sleeve a bit, and Jeremy's a bit more refined, but I'm not aware of any problems", said one. Asked if he'd like to comment on the minor on air contretemps, Mason provided a succinct response; "No". A BBC spokesman said; "This is the sort of thing you come to expect on Newsnight. He [Paxman] wasn't contradicting him [Mason], he was challenging him".

Well that's all right then. Paxman/Mason. Coming to a theatre near you.