An 18-year-old boy has been arrested on suspicion of attacking his parents with a crutch after an argument erupted when he returned home late to their Hong Kong home. The parents ran from their public housing flat in Ling Chuen House in Sha Tin shortly before 11.30pm on Sunday to seek help. The dispute began when the teenager returned home after going out to buy late-night meal for his parents, according to police. “Early investigations showed the boy was accused of returning home late,” a police source said. “In the middle of the argument, he assaulted his parents with a crutch.” Police said the parents suffered injuries to their arms and fled the flat. They sought help from a security guard at the ground floor lobby of the building. The father, 83, and mother, 54, were taken to Prince of Wales Hospital in Sha Tin for treatment. Officers arrested the teenager at home. He was being held for questioning and had not been charged. The case happened less than a year after officers were called to the same flat to handle a report of a domestic dispute. According to official statistics, the number of cases involving the abuse of the elderly across the city rose from 557 in 2015 to 613 last year. Figures from the Social Welfare Department show there were 300 elder abuse cases in the first half of this year. Some 63 per cent of this year’s cases involved physical abuse and 17 per cent was related to money. The figures also showed 12 per cent of the abusers involved their children and 53.7 per cent were their spouses.