Party discipline authorities in Chongqing are looking into an accusation that a district official has been involved in illegal detention and having “improper sexual relation” with a mistress, the Chongqing propaganda website said. Cqnews.net, a website administrated by the Chongqing party propaganda division, said on Wednesday that the Chongqing discipline inspection commission had acknowledged and initiated an investigation into allegations against Lei Zhengfu, the party secretary of Beibei district of Chongqing. The investigation came just a day after senior investigative journalist Ji Xuguang posted a photo on his weibo showing a naked man and woman having sex on bed. Ji said the photo was a screen shot of a video. And he claimed the man in the photo was Lei and he was having “improper sex relations” with his mistress whose last name is Zhao. On another post Ji also questioned Lei over whether he had ordered police to illegally detain Zhao for a month. Ji claimed he had contacted Lei on the phone. “Lei denied knowing Zhao…he said the video was fake…he not only denied my allegation, but also said ‘we could make friends,’ on the phone.” But Ji said he had sufficient solid evidence to support the allegations and would be happy to provide this to the relevant authority. Last September, Ji broke the astonishing story of the Luoyang sex slave case, in which a man kept six women as “sex slaves” in a secret basement prison in the city of Luoyang, Henan province. He also revealed that government officials had tried to suppress the story’s release.