AN undercover agent hired by a Hong Kong-run conservation group to protect the endangered Siberian tiger from poachers has been seriously wounded and his wife and son killed by a bomb believed to have been planted by the Russian mafia. The man, one of 16 armed wildlife rangers employed by the Tiger Trust in the Russian Far East, is in critical condition after the explosion ripped through his Vladivostok apartment on July 14. Michael Day, who runs the British end of the trust, believes the attack was carried out by members of the Russian underworld who he claims are involved in the outlawed trade in tigers for Chinese medicine. ''The young ranger was working undercover investigating the continued slaughter of the last of Russia's wild tigers to supply the underground black market in neighbouring China,'' he said. ''The bomb apparently detonated as he opened the kitchen door, killing his wife and baby boy instantly.'' Mr Day said he was ''stunned'' and ''sickened'' by the attack on the Russian ranger, who he did not want to identify. The bomb marked an ''alarming escalation in the otherwise routine danger normally associated with the job'', he said. ''Confrontations in the field between poacher and game warden often end in violent shootings and sometimes death,'' he said. ''[Last week] we have seen the illegal traders taking the offensive and targeting the innocent family of a man whose only mistake was to work on the side of wildlife. ''This was a deliberate and calculated attack on the innocent family of one of our rangers whose courage and dedication to duty is all that is left between the survival of the tiger and extinction,'' Mr Day said. The ranger was working for the Tiger Trust as part of Operation Amba, an anti-poaching initiative set up by the group. As part of the operation, which is largely funded by the Tiger Trust, the 16 full-time rangers police more than 500,000 square kilometres of traditional tiger habitat. Mr Day said the Russian gangsters turned to trading in the endangered animal after a racket in importing foreign cars into Vladivostok dried up earlier this year. ''The mafia are the middlemen and the executioners, but the Chinese consumers of tiger bone products are as guilty as if they planted the bomb themselves. ''The Year of the Tiger begins in 1998. If the Chinese wish to celebrate this auspicious occasion on the mainland, in Hong Kong and in communities throughout the world, safe in the knowledge that there are still tigers in the wild, then they must act now.'' Caroline Kirrage, head of the Tiger Trust in Hong Kong, said there were only 180 Siberian tigers left and that if poaching was being organised by the mafia and continued at the same rate as last year, the species could be extinct by the end of this winter. Mrs Kirrage believes that although measures taken by the Hong Kong Government to stop traditional Chinese medicine shops from dealing in tiger parts have helped cut down the trade, they have not stopped it. ''It is still going on because the Chinese do not take it seriously. We're trying to take on a 2,000-year-old myth that tiger bones and tiger parts are effective,'' she said. ''There is so much money involved that people are prepared to keep the black market going.''