From Radar Online:
The drama unfolded at the Belvedere Vodka pre-Grammy party at the Avalon on Thursday night which was attended by around 1200 people.
A source told RadarOnline.com: “Jamie and the other guy started fighting about half way through Usher’s set at around 11.30pm.
“The fight spilled to the outside area and I don’t think Usher even noticed because the place was so packed with people.
“When they got outside security intervened and after some cops approached both men seemed to make-up with one another before they left.
