It's the first time the two have seen each other publicly since Hamilton went on "60 Minutes" to accuse Armstrong of doping, an allegation Armstrong has denied repeatedly.

Hamilton's attorney Chris Manderson told ESPN.com that Armstrong repeatedly asked Hamilton how much he had been paid to do the television interview, and added that his legal team would "(expletive) destroy you," "tear you apart on the witness stand," and "make your life a living (expletive) hell."

Manderson also said his team formally notified federal authorities on Monday about a weekend incident.

"Lance Armstrong is a possible defendant in an investigation that's been widely reported, and Tyler is a probable witness," Manderson said. "When there's any contact, especially aggressive contact, we as lawyers have a duty to inform the authorities. ... What they will do with it, I don't know."

A co-owner of the bistro where the incident took place told ESPN that the body language of the two men was not combative, was not hostile and there were no threats. She also said she did not hear the entire exchange.

Armstrong downplayed the incident, calling it "certainly awkward for both of us" and "truly uneventful" in comments reported by Outside Magazine writer Abe Streep.

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