Keith Raniere, the leader of an elusive US self-help group, has been arrested by the FBI in Mexico and charged with sex trafficking. Federal prosecutors allege Mr Raniere oversaw a "slave and master" system in his group called Nxivm, where female members were expected to have sex with him and were branded with his initials. He is expected to appear in court on the charges in Texas on Tuesday. Mr Raniere left the country last year after former members spoke to US media. A number of women came forward for an investigation published in the New York Times newspaper in...