Gatlin expresses shock over latest doping allegations

American world 100m meter champion sprinter Justin Gatlin says he is "shocked and surprised" at doping allegations made against his coach and an agent. 
Athletics anti-doping officials have begun an investigation into what the president of the sport's governing body called "serious allegations" about Dennis Mitchell and Robert Wagner.

A video released by The Telegraph features a man the newspaper says is Wagner insinuating Gatlin is taking banned drugs, "just like every other sprinter in America".

The paper also said Gatlin's coach, former Olympic gold medallist Dennis Mitchell, told reporters that athletes are able to get away with doping because the drugs they use cannot be detected by tests. Both deny the allegations.

Writing on instagram on Tuesday, Gatlin said he "fired" Mitchell "as soon as I found out about this". The 35-year-old American said he is "not using and has not used" performance-enhancing drugs. He added: "all legal options are on the table as I will not allow others to lie about me like this."