Primitive animal traps found across the city - including in Mid-Levels - have severely injured at least eight stray and pet dogs in the past two years.
Three were found in such pain, with a leg crushed in the jaws of the rusty steel traps, that they had to be put down by the Society for the Prevention of Cruelty to Animals (SPCA).
Since 2009 only one person has been fined - the penalty was HK$1,600 - for setting animal traps illegally under the Wild Animals Protection Ordinance.
But the SPCA said it would continue to step up inspections on hillsides and in the countryside to clamp down on the cruel and unlawful practice.
Tony Ho Tse-tong, chief officer of the SPCA Inspectorate, said he thought the traps were put out by people who wanted to eat wild animals.
One of the traps was found on a hillside near Conduit Road in Mid-Levels in November 2010. Others have been found in the countryside in Sha Tau Kok, Tuen Mun, Tai Po, Sai Kung and Yam O on Lantau Island.
The SPCA is alarmed by the gradual increase in the number of traps being reported, from four last year to six in the first eight months of this year.