The decomposed bodies of more than a thousand ducks have been found on a river in Pengshan county, Sichuan, following the dumping of more than 10,000 pigs in the Huangpu River in Shanghai earlier this month.
Even though the dead ducks were first discovered almost a week ago, most county residents said the local government had not told them about the incident.
A county government publicity official told the website of the People's Daily that the ducks had been found in the Nanhe River on Tuesday, their bodies littering the river's banks between the towns of Qinglong and Guanyin.
Zhang Jichuan, the county's deputy director of environmental protection, said the bodies were rotten and smelly when discovered.
"Judging by the level of decomposition, the ducks must have been dead for days and they were not dumped by people living nearby," he said.
The authorities also found more than 60 sacks nearby that may have been used to transport the dead animals.
The county government officials said they suspected that the ducks had come from a farm in another county that had recently experienced a disease outbreak.
All the ducks had been removed from the river and safely disposed of in a cave, the county government said.
A restaurant owner in Pengshan said by phone that he was worried that the dumping of the dead ducks may have polluted the water.
Drinking water for urban residents came from a reservoir on another river, he said, but the Nanhe was a major source of drinking water for some farmers living along its banks.
The water was also used for agricultural production.
In the wake of Shanghai's dead pig crisis, the dumping of dead ducks in Pengshan received extensive media coverage over the past few days, with extensive reports on China Central Television.