Police have arrested 30 people, including 20 students, the youngest of whom was only 12, in raids on a network allegedly supplying ketamine in Sheung Shui. Police said charges against those arrested involved at least 14 alleged instances of trafficking and three triad-related offences which had occurred over the past four months. Further arrests could be made as another 10 suspects, including the alleged ringleader, were being sought. An officer involved in the investigation said the syndicate was controlled by Wo Shing Wo triad society. On Wednesday evening police raided 10 places, including internet cafes, amusement game centres, parks and flats in Sheung Shui, Fanling, Tuen Mun and Kwai Chung. The 30 suspects included 20 students and several youths aged 12 and up. Twelve, including six students, were arrested on suspicion of drug trafficking. Another 18 suspects, including 14 students, were allegedly involved in illegal assembly and other triad-related offences, such as claiming to be a member of a triad society and inciting others to become triad members. Ketamine, Ice and Ecstasy worth about HK$10,000, were seized during the operation. Superintendent Steve Li Wing-hong, of New Territories North regional crime unit, said he believed the operation had cracked a major ketamine supply ring. He said a number of youngsters were recruited in places like game centres and internet cafes during the summer break to sell ketamine among their peers. 'We believe it is a tactic to avoid police detection.' Officers had not uncovered any drug trafficking in schools. Meanwhile, four youths aged 15 to 19 were arrested in Ho Man Tin later in the day for possession of drugs and 15 grams of ketamine was seized. Police said the younger three were Form Four students and the 19-year-old had a triad background.