A man arrested in Delhi on suspicion of killing a six-year-old girl has told police that he sexually abused the corpses of a dozen children he murdered over the past seven years. The confession of 23-year-old Ravinder Kumar, a slightly-built bus cleaner, was a grim echo of the serial killings at Nithari in 2006, officials said. He apparently told police he lured children with candy, killed them if they resisted and had sex with the bodies.Police said Kumar committed his first crime in 2008, but it went unreported.