Cycling: Death threats to doping chief

American cyclist Lance Armstrong who has been banned from the sport for life (Rex Features)

The head of the US Anti-Doping Agency tightened security within his organisation after receiving several death threats during the investigation into Lance Armstrong.

In an interview published yesterday in French sports daily L'Equipe, USADA chief executive Travis Tygart said the FBI had been called in after a series of threats were made to him and predecessor Terry Madden.

"Am I a target? I won't shirk my responsibility," Tygart said. "The most important thing is to protect my team. And to maintain the respect of the athletes who don't cheat."