More than 2,000 dead pigs were found in a river near Shanghai.

The BBC reported that workers have been collecting the dead pigs from the Huangpu River as it is a major source of drinking water for the city. The mysterious pig carcases are under investigation but the BBC reported that it is believed that perhaps farmers were dumping the pigs upriver.

Workers aiding in the cleanup were on boats using rakes to pull out the pig carcases which came into view on the rive, Thursday. Many of the pigs have washed to the shore.

"We have to act quickly to remove them all for fear of causing water pollution," Xu Rong an environmental official said to the Global Times Newspaper.

The BBC reported that the pigs may have come from farms in the Zhejiang province.

"Is this water still drinkable after dead pigs were found floating in it?" 60-year-old Liu Wanqing said to the y state-run China Daily newspaper. "The government has a responsibility to conduct a thorough investigation and provide safe water to residents."

Fears of pollution are rising and an official at the Songjiang environmental bureau declined to comment when asked by Reuters.

"The Shanghai government said in a statement posted on its website on Monday that workers were continuing to collect carcasses from the river and it was closely monitoring the water quality although no pollution has been found so far," reported Reuters.

Reuters reported that contamination in water caused by fertilizer and chemical spills is a concern in China and the government has plans to invest $850 billion over the next decade to improve the water supply system.

Bloggers across the Internet had a lot to say about the pig carcases, mainly criticism about the government response.

"Related government departments should seriously investigate this and get to the bottom of it," said one blogger named Ting Tao. "The government should really pay attention to people's lives and take no time to solve food safety issues."