Former cycling doper turned whistleblower Tyler Hamilton described Dr Eufemiano Fuentes as a "one-man Wal-Mart of doping" in his 2012 book The Secret Race, which detailed the use of performance-enhancing drugs in the sport.
Hamilton was among 11 former teammates who testified against Lance Armstrong during the US Anti-Doping Agency's investigation.
In his only UK interview, he gave ITV News his reaction to Armstrong finally confessing.
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The book by Cameron comms chief Sir Craig Oliver reveals that Mr Cameron was frustrated with Theresa May's neutrality during referendum.
Cloud and outbreaks of rain will ease away eastwards during the morning, clearing the east coast around midday with sunny spells developing.
Police and emergency services are attending the scene.