Two passengers from Hong Kong were arrested in Canada after nearly C$64 million (HK$345.6 million) in heroin was found on a London-bound plane. Customs inspectors found 60 bricks of heroin hidden in six toilets on the Canadian Airline DC10, which had arrived at Toronto's Pearson international airport from Vancouver. The suspects, Lee Shu-tong and Wu Jing-jun, both 34, were charged with a number of drug-related offences. Their nationalities were not revealed. It is understood they bought their flight tickets a day before setting off from Hong Kong to Vancouver, where they changed on to the Britain-bound flight. It is not yet known how the plane was boarded in Hong Kong with 43 kilograms of heroin apparently in carry-on baggage. Customs spokesman Michel Cleroux said flight attendants alerted police after noticing the two men made several trips to the toilets with their baggage in the four hours it took to fly from Vancouver to Toronto. It is believed they pulled off wall panels to hide the drug. Royal Canadian Mounted Police spokesman Michelle Paradis said: 'It is a fairly significant seizure. We don't know if it is the biggest one yet, but it has to be one of the biggest.' Last year Customs officials made 4,594 seizures of illegal drugs across Canada.