* Italy prosecutors accuse four officials of kidnapping him * Charge sheet accuses one official of involvement in murder * Egyptian officials, police deny any involvement in killing * Trial set to start on Oct. 14 (Recasts with judge ordering trial) By Crispian Balmer ROME, May 25 (Reuters) - An Italian judge on Tuesday ordered four senior members of Egypt's security services to stand trial over their suspected role in the disappearance and murder of student Giulio Regeni in Cairo in 2016. Regeni, a postgraduate student at Britain's Cambridge University, disappeared in the Egyptian capital in January 2016. His body was found almost a week later and a post-mortem examination showed he had been tortured before his death.