Customs officers made Hong Kong's largest seizure of cocaine after finding 160kg of the drug with a street value of HK$111 million hidden inside two containers carrying bottled mineral water from Panama, officials said yesterday. Customs said 640 slabs of high-grade cocaine were hidden inside 160 hollowed-out wooden components in 80 pallets supporting the bottles. The haul was 14 times greater than all the cocaine seized during the first six months of this year, officers said. Seven locals - two drivers, their employer, employees from a logistics company and the local representative of the goods' owner - were arrested. The five men and two women, aged 23 to 51, were released on bail. Ben Leung Lun-cheung, head of the Customs Drug Investigation Bureau, said it was Hong Kong's largest seizure of cocaine. 'We thought it was highly suspicious that bottles of mineral water would be transported thousands of miles to Hong Kong. The drug syndicate's method of trafficking using the wooden frames was sophisticated and rarely seen.' Mr Leung said the drug was destined for places outside Hong Kong, but gave no details. He said the seizure was a devastating blow to the international drug-trafficking syndicate. 'This sends a very clear message to drug traffickers that they will suffer a great loss and pay a big price,' he said. Given a wholesale price of about HK$210 a gram, the syndicate would have made a profit of HK$77.9 million on the haul, customs said. The consignment was discovered after officers stepped up inspections on cargo from countries known to be the source of illegal drugs, in an operation codenamed 'Hippo' this month in which 45 containers from 23 vessels were inspected. The two containers arrived on a ship from Panama on July 16 and was inspected at Kwai Chung on July 24. Suspicions were raised after the shipment of more than 2,000 bottles of water, at a cost of US$6,000, carried a delivery charge of only HK$20,000. Officials said two wooden bars at the centre of each pallet were found to be hollowed out after an X-ray examination and a sniffer dog then alerted handlers to the haul. Mr Leung said two slabs of cocaine had been packed in a metal case and two cases had been hidden in each of the wooden bars, which had then been sealed with superglue. The previous largest seizure was made in December 1998 when 150kg of cocaine was found hidden in an aircraft tyre at the airport.