In 2020, North Korean soldiers shot dead a South Korean fisheries official named Lee Dae-jun when they found him in their territorial waters-- an incident so shocking it later prompted Kim Jong Un to apologise. But the details are sketchy and mostly classified. Exactly how and why the official came to be floating in a life jacket above the sea border has become a bitter political debate in the South. South Korea's former spy chief Park Jie-won is now a subject of an investigation into the former government's handling of Lee's killing. The intelligence services claim that Park destroyed evidence showing Lee had no plans to move to Pyongyang. Park dismisses the allegations as unfounded. "The probe is aiming at Moon Jae-in the person. That's how I see it," says Park. IMAGES AND SOUNDBITES