Lusaka – Zambian authorities have reportedly arrested yet another opposition leader, who is a fierce critic of President Edgar Lungu, in the latest sign of a crackdown on dissent. Writing on his Facebook page Saviour Chishima, leader of the United Progressive People (UPP), said that he had been arrested and was being taken to the police headquarters in Lusaka.See post below In a brief interview with News24 on Thursday, Zambian police spokesperson Esther Mwata confirmed Chishima's arrest but failed to say on what charges the opposition leader was being held. Mwata said that the police were still interrogating the opposition leader before pressing any charges. "The police are still talking to him now, I am unable to tell you what charges he would be charged on. I am not going to be saying anything on this, the police are still questioning him," said Mwata. UPP spokesperson Kizito Mukuka said that the vocal opposition leader was arrested on the premises of a privately owned television station in the capital Lusaka, according to a BBC report. He added that Chishima had gone for a pre-recorded interview at Diamond Television and was picked up by plain-clothed police officers soon afterwards.This came as the leader of Zambia's main opposition, the United Party for National Development (UPND), Hakainde Hichilema, was recently arrested and charged with treason.Authorities alleged that the wealthy businessman blocked Lungu's motorcade with his own convoy of vehicles during a traditional ceremony in the country's western province in April.They said that Hichilema's motorcade did not yield after presidential security guards signalled for it to get out of the way.Hichilema was moved to a maximum security prison in June and it was unclear when he would be back in court.