The mother of nine-year-old Lee Ka-kit, who died on Thursday after his school bag was believed to have dragged him over safety railings 20 floors to his death, said yesterday the barrier should be made higher to prevent others from falling. Police investigating the tragedy have examined the bag, which was packed with heavy textbooks, to see if it could have caused the boy to lose his balance and topple over the 1.22-metre-high railing at his Tuen Mun public housing block when he leaned over to glance down. It weighed in at 3.86kg. Ka-kit's mother, Wu Yuk-ping, 33, said she did not believe the boy would have committed suicide and said he was not unhappy at school. Asked whether she thought the railings were safe enough, the housewife said: 'They are too low. The railings should be made higher to make them safer. 'I don't want to see what has happened to us happen to someone else,' she added. Tuen Mun District Councillor Leung Kin-man and other tenants in Wu King Estate agreed that a higher sets of railings should be installed. Mr Leung, who also lives in the estate, said he had discussed the height of the railings with the estate manager on a number of occasions in the past but he had always insisted they were high enough. 'After the tragedy, I think it is the right time for them to consider reviewing the height of the railings.' Mr Leung said he would listen to the opinions of tenants on the estate before beginning another round of negotiations with the Housing Department. One mother-of-two who lives on the 18th floor of Wu Pik House, where the tragedy occurred, said the railings should be made about a metre higher to improve safety, but she was opposed to the installation of ceiling-high railings. 'Safety is always my first concern. I have warned my two children after the incident,' the housewife said. A maintenance surveyor from the Housing Department, Maxwell Chiu Ying-cheung, said that the department would not consider installing higher railings at present because the existing 1.22-metre-tall barriers were already taller than the legal requirement of 1.1 metres. He said some residents on the estate had told department staff they did not want to see higher railings, which would make them feel as if they were living in a prison. Mr Chiu said they would do more to remind tenants to take care of their children. An elderly woman who reportedly witnessed the boy's fall was still being sought by police yesterday. Officers were trying to establish the point from which the boy fell. It is not known why he leaned over the railings, although some residents said they had seen youths leaning over them in the past to look for each other when on different floors.