New Delhi, Nov 23 : The mother of the 17-year-old boy, who was reportedly stabbed over 50 times by a 16-year-old boy during a street robbery, said on Thursday that her son had gone to buy groceries for which she had given him money. "My son went out to buy flour and milk at 6 p.m. on Tuesday. I had given him money, but he didn't return. I inquired with everyone, but no one knew where he was," the deceased's mother said. "The police informed me the next morning that my son had been stabbed. They asked for some identification mark, and I mentioned that he had a tattoo that read 'meri jaan mom'," she said. "I want justice for my boy, especially given the brutal manner in which he was killed. In a video clip, the accused claims that this is his fourth murder. I demand justice... He should be sentenced to death. But the police say that he is a juvenile. He will be released from jail in a year and may kill someone else's son," she said. Two of days after the 16-year-old boy was arrested for stabbing the teenager for over 50 times, disturbing visuals surfaced on Thursday showing the accused dancing over the body, "celebrating" the heinous act. In the CCTV footage, the accused minor could be seen dragging the body into a narrow lane and repeatedly stabbing the victim on the neck to ensure his death. He also kicks the lifeless body on the head multiple times. The disturbing scene concludes with the assailant standing over the body and engaging in a macabre dance. The incident took place at Janta Mazdoor Colony in North-East Delhi's Welcome area. "The minor accused has been apprehended and the knife used in the crime has been recovered from his possession," said Deputy Commissioner of Police (North-East), Joy Tirkey. "The reason behind murder was robbery. The boy first choked the victim and when he fell unconscious, he stabbed him multiple times before robbing him of Rs 350," the DCP said. "The victim was taken to GTB Hospital where he was declared brought dead," he added. /IANS