Workers in China have been working all weekend pulling out the dead carcasses of 2,813 pigs from a river near Shanghai.

According to a statement by the Shanghai Agriculture Committee, some 900 dead pigs had been removed from the nearby Huangpu River on Saturday. By the end of the day, an additional 1,200 were recovered. The Huangpu River, which is also the Shanghai drinking water source, had dead pigs in the water as early as Thursday, when they were first spotted.

Dead Pigs in Huangpu River
Nearly 3,000 dead pigs were pulled out of the Huangpu River near Shanghai as of March 10, 2013. Reuters/Aly Song

By the the end of the weekend, almost 3,000 pigs were recovered. The discovery has been a big concern for the 23 million Shanghai residents for various reasons, starting with the biohazard concern that threatened the city’s drinking supply. However, according to the China Daily, authorities have assured residents that the pig infestation has not affected the quality of the water. The Shanghai Daily also reported that no cases of animal epidemic outbreaks have been diagnosed in the city.

Dead pigs in Huangpu River
Nearly 3,000 dead pigs were pulled out of the Huangpu River, a Shanghai drinking water resource, as of March 10, 2013. Weibo

The origin of the pigs has yet to be determined, several local news outlets suspect that the livestock floated to Shanghai from nearby farms in Zhejiang province. The Shanghai animal-disease control authorities, however, determined a pig virus, porcine circovirus -- a common disease among pigs -- to be the reason behind the animal corpses found in the river. The virus, which is not known to be infectious to humans, was found when testing the water in a certain area of the Huangpu. Testing of the river has been conducted on an hourly basis, Bloomberg says, and has come up negative for other dangerous diseases like foot-and-mouth, swine flu, hog cholera and blue ear.

Though there appears to be no human threat, many people on China’s Twitter-like social media platform, Weibo, are not satisfied with the speed of the government response. After initial sightings on Thursday, the actual retrieval of bodies did not occur until Saturday. The lapse in action has left many bloggers on Weibo, especially those living in Shanghai, disgusted.

“Is the water really safe? Letting dead pigs stay there for several days just does not seem right!”

“I feel like moving quickly was of importance here. Pay attention government! This is dangerous!” A blogger remarked.

“Water pollution is already a problem,” one blogger said, referencing the nation’s most recent headline-grabbing environmental movement to fight water pollution, “Now pigs? This is getting ridiculous,” he said.

Local authorities were reported to still be retrieving dead pigs from the river as of Sunday.