TRIADS are using children as young as five years old to traffick dangerous drugs, according to police. Wan Chai police assistant district commander Superintendent Leung Hung-wai said two girls aged between five and seven were caught with drugs this year. He warned there was a growing trend for triad societies to use children and students to traffick drugs because people were less suspicious of them and police were less inclined to check them too closely. Two girls aged between 16 and 20 were also arrested this year for trafficking, and police figures show an eight-fold increase in the number of young people aged between 16 to 20 arrested for possession of dangerous drugs in Wan Chai district. The number of triad-related offences committed by students - such as criminal intimidation and blackmail - has also been on a steady rise in the past two years, from nine cases in 1991, and 12 last year, to 15 cases at the end of this year's third quarter. Despite the triad trend towards using pre-teens and teenagers for illegal activities, Superintendent Leung said triads had not really penetrated schools in the district. ''Our investigations in Wan Chai district show little triad activity in schools. However, there might be some students who claim to be triad members just to scare others away. These students have not formally joined triad societies,'' said SuperintendentLeung. The number of robberies and shop theft cases committed by students has also risen in the district: the number of shop thefts doubled from 22 in the third quarter last year to 45 for the same period this year. The number of robberies increased by more than 200 per cent from last year's four cases to 14 cases this year, but Superintendent Leung said the situation was not as bad as the figures indicated, because the young robbers were not serious criminals. Some of the students stole pocket money from school children at knife-point, but they did not mean to commit serious and violent crime, he said. Superintendent Leung said part of the problem was peer-group pressure on children to behave badly. He said police were considering relaxing the age criteria of the Superintendent Discretion Scheme, a programme under which police supervise young offenders' behaviour without official charges being laid.