A pornography-obsessed 38-year-old Briton has stabbed and strangled his teenaged niece to death to fulfill his sick obsession, a media report said.

John Maden, who had downloaded a collection of sadistic 'snuff' movies from the internet, enticed his 12-year-old niece Tia Rigg to his home on the pretext of getting her to look after his daughter, Daily Mail reported on Monday.