Firemen rescued a three-year-old boy locked in a flat which caught fire in Tai Kok Tsui yesterday, prompting fresh concern about the plight of home-alone children in Hong Kong. The boy was found alone and unconscious. He had suffered severe smoke inhalation. He was taken to Kwong Wah Hospital, where he remained in serious condition last night. Police arrested the boy's 20-year-old father and the man's 17-year-old girlfriend on suspicion of child abuse when they went to the flat after the fire was put out. Police said the child appeared to have cane marks on his body. Neighbours raised the alarm soon after midnight when they heard the boy cry for help and saw smoke billowing from the flat. Firemen found the boy lying in the dining room, his face and limbs blackened by smoke. Police estimated the fire had broken out within 10 minutes of the couple leaving the boy unattended. A preliminary investigation by firefighters suggested the fire had been caused by a cigarette butt left burning on a bed. Police said they had contacted the boy's mother. The Social Welfare Department said it would work with the police to follow up the case. It is the third time in a month a child or children have suffered injury after being left at home alone. On August 26, two children, aged two and three, suffered serious burns in a fire in a locked flat in Tuen Mun when their mother went to work. On August 31, rats bit the toes of a 24-day-old baby boy in Sha Tin after his mother reportedly left him unattended while she took her three-year-old daughter to kindergarten. Susan Choy So Suk-yin, director of the Society for the Protection of Children, urged the government to provide better child-care services and to do more to educate teenage parents, single parents and new migrants with children. A recent survey of nearly 600 Tuen Mun parents found more than 70 per cent were dissatisfied with community child-care services. They said existing services were often located too far from where they lived and that their operating hours were too short. Ho Foi-lin, spokeswoman for the Concern Group on Women in Poverty, which conducted the survey, said the government should put more resources into child-care services and provide child-care subsidies to needy families. 'If it doesn't, then many children may have to stay at home alone while their parents work. Tragedies may happen again,' she said.