Police seized HK$640,000 worth of ketamine and arrested seven people, aged 17 to 27, for drug trafficking after raiding a drug storage centre in Tin Shui Wai. Officers took action after a month's investigation and set an ambush outside a house in Sun Wai Ha Tsuen yesterday. A 23-year-old man was seen driving to the house and unloading a box with the help of a 19-year-old man. When they were about to leave the house, officers stopped and arrested them, broke into the house and confiscated 5kg of ketamine inside the box and found another 0.75kg of the drug in the house.