Local authorities in southern China began seizing and drowning the first of thousands of civet cats on Tuesday in an emergency slaughter triggered by an unpublished study suggesting the weasel-like animal may be the source of the SARS virus.

The extermination of about 10,000 civets, which are served as a delicacy in wild game restaurants in Guangdong province, began despite warnings from the World Health Organization that killing the animals might make research of the disease more difficult and could help spread the deadly virus if safety precautions were not taken.

Several hundred civet cats were killed Tuesday, state media said, and police were stopping vehicles on highways to prevent smugglers from entering or leaving the province with the brown, long-tailed animals that residents believe can ward off illness if cooked and eaten.

Meanwhile, hospital officials reported that the only person in China known to have contracted the illness in five months had recovered and would be released Thursday. The 32-year-old television producer was quarantined in Guangzhou, the provincial capital of Guangdong, on Dec. 20 and health authorities confirmed Monday that he had the disease, severe acute respiratory syndrome.

Even before the diagnosis was announced, a team of researchers in Guangzhou and Hong Kong reported finding a genetic link between viruses taken from civet cats and fragments of the virus taken from the patient. Provincial authorities quickly ordered all wild game markets closed and all civets and other related species on farms, in markets and in restaurants to be put to death by Saturday.

"Guangdong is entering an extraordinary period, and extraordinary measures are called for," Feng Liuxiang, a provincial health official, was quoted saying in state media.

The official Guangzhou Daily newspaper said all civet cats in the city were being taken to a central plant and drowned in their cages in vats of disinfectant. Their carcasses were placed in a pressure cooker set at 392 degrees, destroying them and killing all bacteria. The remains were being processed at a sewage plant, the newspaper said.

Samples of the civet cats' excretions were being collected for research purposes, and all materials that came into contact with the animals were destroyed in an incinerator, the newspaper said.

While workers carrying out the slaughter were shown in state media wearing white protective suits, goggles, surgical masks and elbow-length rubber gloves, police officers and other workers collecting and caging the animals wore only surgical masks and gloves, and some were not wearing those.

WHO officials have urged the Chinese government to ensure that personnel are properly trained and protected from exposure to the virus, and that any slaughter take place in a controlled environment to avoid contamination of air, water and soil.

They have also noted that scientists have not proved that civet cats can transmit the virus to humans. In addition, they have not ruled out the possibility that other animals, including humans, infected civets. As of August, tests had been conducted on about 600 civets, too small a sample to draw firm conclusions, and 30 to 40 of the animals were found carrying a virus similar to SARS, according to WHO.

China tried to hide the SARS epidemic when it began in late 2002, allowing the virus to spread to at least 27 countries and sicken more than 8,000 people, including 774 who died. The government eventually abandoned the coverup and launched an aggressive campaign that appeared to wipe out the virus in July.

Health officials have been unable to determine how the latest patient was infected. They said he had no known contact with civet cats.

Wearing a mask to protect against the SARS virus, a woman kisses her son at a train station in Beijing. A civet cat looks out from a cage at a market in Guangzhou in Guangdong province, where local authorities slaughtered hundreds of the animals.