The horror continues.
Thousands of dead pigs are still turning up in Shanghai's Huangpu river, after hundreds of carcasses were initially discovered there last Thursday.
The number of dead pigs is now up to 5,916, authorities said Tuesday, according to Chinese news agency Xinhua.
That's more than double the number reported on Monday.
The possible sources of the carcasses are still under investigation.
Clean-up workers are moving fast to remove the dead animals to prevent water pollution. Most of the dead pigs are whole, which is good because it means the inside parts aren't falling out into the water.
The Huangpu river is a critical source of drinking water for Shanghai's 23 million residents. Authorities are conducting hourly water quality tests, according Shanghai's official website, and say the city's tap water is still safe to drink, despite the rising death toll.
Officials found a virus in a water sample called porcine cirovirus, Xinhua reported, but that virus has not been known to infect or cause disease in humans.
Tags on the pigs' ears show that the animals came from Jiaxing, a neighboring province of Shanghai. This suggests that the corpses were dumped into local rivers by farmers. It's not clear what the pigs died from to begin with. There's no evidence that they jumped in the river and drowned.
Jiaxing authorities said that the pigs were dumped, but the tags only point to the animals' birthplace, Xinhua reported.
In recent years, China has moved toward larger, industrial pig farms in order stabilize pork prices.
Between 2009 and 2010, the country produced somewhere between 490 million and 618 million pigs, according to the Food and Agriculture Organization of the United Nations.
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