OPERATION Spectrum, a police task force set up to catch the Melbourne killer who abducted Hongkong-Australian girl Karmein Chan, is to be scaled down. The 35-member Victoria Police task force was set up after 13-year-old Karmein was abducted from her east suburban home on April 13, 1991. Her body was found in a grave a year later. She had been shot. Since then the police operation has cost about A$3 million (HK$15.6 million), with detectives checking more than 30,000 houses across 15 suburbs. But they appear no closer to catching the man, dubbed Mr Cruel, who killed Karmein and possibly abducted at least two other children in east Melbourne. A police spokesman said the task force would still remain a separate, specialised group and would be expanded immediately if any new information came to light. ''Certainly it will never be forgotten or neglected.'' Task force detectives have compiled about 10,000 information reports and driven more than 600,000 kilometres in their hunt for the killer. John Chan, Karmein's father who migrated with his wife Phyllis, did not wish to comment.