THE largest single reward ever offered to solve a murder in Canada has been posted by police investigating the killing of 22-year-old Miss Sylvia Leung Sze-hon, the daughter of Hongkong immigration chief Mr Laurence Leung Ming-yin. Miss Leung was stalked and struck by the bolt from a powerful crossbow in the car park of the British Columbia Institute of Technology near Vancouver on January 24. Royal Canadian Mounted Police (RCMP) Staff Sergeant Michael Eastham said C$300,000 (HK$1.83 million) was pledged for information leading to the arrest and conviction of the person or persons responsible, and included an offer of witness protection. A spokeswoman for Mr Leung said the reward money, if not used within six months, would be donated to the Sylvia Leung Memorial Fund for students at the institute. ''Mr Leung stressed the murder was not related to his work but said he hoped someone would be able to help with information,'' she said. Sergeant Eastham only said the money ''came from people who are very interested in what is happening in our community and people who are very concerned with the death of Miss Leung''. But an official from the main Chinatown branch of the Hongkong Bank of Canada confirmed that all funds raised so far came from Hongkong, adding that more was likely. Police have been unable to locate the murder weapon or identify any concrete suspects after 11 weeks of investigation, but said that they had new information regarding a possible motive which could not be revealed. ''But that amount of money should trigger something forward,'' said Sergeant Eastham. ''Anybody who comes forward with information and helps us convict the culprit will be protected. We will relocate them if we have to,'' he said. Canadian authorities said they have been unable to link her death to a series of at least five vandal attacks against the family's Vancouver residence, which was listed for sale when the Leungs returned to Hongkong last month. Sergeant Eastham denied ''any kind of offshore love-triangle'' was suspected, adding that the majority of the reward notices will be posted in Vancouver.