FBI looking into incident between Lance Armstrong and accuser

Tyler Hamilton, the former bike racer who said on "60 Minutes" that he took banned substances with then-teammate Lance Armstrong and knew of a positive drug test that was covered up, ran into Armstrong at a bar in Aspen on Saturday night. Words were exchanged, and now the FBI is trying to ascertain if the incident constitutes witness tampering. Hamilton is a witness in federal grand jury proceedings in Los Angeles that are thought to center in part on Armstrong.

Photo of Armstrong