At the start of President Obama's interview on the "Late Show with David Letterman," the host asked his guest whether he wanted to say anything to the empty chair next to him.
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Vitaly Stepanov, who helped uncover the Russian doping scandal, says the IOC is less concerned about ridding world sport of drug cheats.
Colombian drug lord Daniel Barrera Barrera was fined $10m for manufacturing hundreds of tonnes of cocaine that he trafficked globally.
The 37-year-old Somali immigrant to Canada died after being beaten by several police officers, according to local media reports.