A teenager who trapped a six-year-old boy in a drainage ditch for 50 hours without food or water has been sent to a detention centre. The 14-year-old Nepali received the indeterminate sentence yesterday after his lawyer told Kowloon City Juvenile Court that he was full of remorse and had vowed to change his life. He had pleaded guilty to one count of false imprisonment and one of attempting to cause grievous bodily harm with intent. Magistrate Ronald Cheung Wai-tat cancelled an earlier order, imposed on a theft charge, that required the defendant to live in a boys' home but said he would have to continue to observe a related curfew when he was released from the detention centre. Lawyer Raymond Ng Chi-hin said the incident started with a minor argument. "After he was arrested, he co-operated with the police and helped to recover the victim and admitted [what he had done] in full," the lawyer said. He said the boy was very remorseful and afraid of being put behind bars, which had made him determined to quit the bad company he had been keeping. "He has started to think about his future now, with his family's support," he said. The court heard that the defendant argued with the six-year-old in a Yau Ma Tei park on the night of July 29 after the younger boy used foul language to the teenager's two eight-year-old friends. He lured the boy with chocolates then beat him up and dumped him in the concrete ditch. He sealed him in with two drain lids weighing about 15kg. He told the victim: "Don't go away. I will beat you to death." He told no one what he had done until he was arrested on July 1.