Chilling CCTV footage released by police shows the moment a masked gunman walked calmly into a crowded London park before shooting a 15-year-old boy in the chest.
The killer, wearing a dark cap and balaclava, had a handgun concealed in his jacket pocket as he strolled through the children’s play area at Emslie Horniman’s Pleasance Park in Ladbroke Grove, where hundreds were celebrating at a family fun day.