A policeman has been arrested for killing a radio commentator on a central island last month, officials said on Thursday. Darwin Quinoyog, posted at the Magsaysay police station on Mindoro island, was arrested last week, Arnel Dalumpines, head agent of the National Bureau of Investigation, told reporters. “We have a strong case against him after several witnesses, including the victim's wife, saw him shoot Crispin Perez dead in front of his house,” Dalumpines said, adding the suspect faced life imprisonment if found guilty. Dalumpines said investigators were trying to establish the motive for the killing of Perez, who hosted a daily morning radio talk show at a government-owned network. At least six journalists, most of them radio commentators, have been killed in the Philippines since January this year, making the country one of the most dangerous places in the world for the working press. The National Union of Journalists in the Philippines (NUJP) said five journalists were killed last year and 59 have been killed since 2001, when President Gloria Macapagal Arroyo was swept into power. Investigative stories on drug trafficking, corruption and other illegal activities often puts reporters at risk.