Updated at 7.20pm: Hong Kong police have mounted operations with its mainland counterparts against two trans-national drug-trafficking syndicates in the past few months, a government spokesman revealed on Thursday. The spokesman said that since late 2004, Hong Kong police officers had been targeting the syndicate. It is suspected of planning to ship ketamine from a Middle East country to China via Hong Kong. He said details of drug shipments and other relevant information were referred to the Beijing Ministry of Public Security, Guangdong Provincial Public Security Department and Guangxi Public Security Bureau. Mainland authorities arrested eight people, including the syndicate head, in late March. They found 400 kilograms of ketamine in two containers, which were transported from Guangxi to Guangdong. The ketamine was worth about 100 million RMB (HK$94 million) in Guangdong. In a much-diluted form, the drug could fetch up to HK$250 a gram in Hong Kong. During follow-up operations, mainland authorities seized 370kg of liquid methamphetamine and a quantity of arms and ammunitions. The drugs originated in India and were destined for illicit markets in Guangzhou, Shenzhen and Hong Kong. Further inquiries by the Guangdong Provincial Public Security Department led to the arrests of another 12 syndicate members; all were mainlanders, the spokesman said. It was believed that the syndicate has been successfully smashed, he said. During another joint operation in March, Hong Kong police officers and the Shenzhen Public Security Bureau (PSB) smashed a syndicate involved in the smuggling of heroin and methamphetamine (Ice) from the mainland to Hong Kong and other countries. The operation became overt when the syndicate members delivered the drugs to a Hong Kong buyer in a hotel in Shenzhen. Shenzhen PSB officers arrested two mainlanders, a Vietnamese and a Hong Kong man, seizing 7kg heroin with about HK$2 million, the spokesman said. During further searches, Shenzhen PSB officers seized 56kg of methamphetamine (Ice) at a flat in Shenzhen this month. Four Hong Kong people and a mainlander were arrested. Simultaneous police operations were launched in Guangzhou with another seizure of 5kg of Ice. The drugs seized in the two places were worth about HK$20 million. Investigations into both cases were continuing on Thursday afternoon, the spokesman added.