No cover-up
The Shanghai government has also denied claims of a cover-up as alleged in a newspaper report.
The People's Daily reported the Shanghai government was slow in reacting to the crisis.
"There is still much room for the Shanghai government to improve its way of releasing information," the paper said.
But the paper also quoted Xu as saying that "Shanghai has never tried to cover up any information in the dead pig dumping scandal, but follows the principle of working transparently to the public."
The city government has been updating the situation regularly on its official microblog since March 11, three days after a netizen posted pictures of the dead pigs that drew the attention of local residents and authorities in Songjiang.
Stopped fishing
Zhejiang Province's Jiaxing City, located in the upstream of the Huangpu River, is believed to be the source as some ear tags showed the dead pigs were raised there.
Local fishermen in Jiaxing had stopped fishing and were instead helping in digging out the pig bodies from the river, Xiaoxiang Morning Herald reported yesterday.
The fishermen took up the job of retrieving the pig carcasses, earning an extra income of up to 150 yuan (US$24) daily.
They also told the paper that the water there was too polluted to fish.
The newspaper compared the rivers in Jiaxing to a "black mirror" of pollutants including garbage, pig manure and dead pig bodies, hurting the livelihood of the fishermen.
Fengnan Village had about 246 fishermen. But now only 60 of them went out fishing while the rest joined in hunting for dead pigs.
"How can fish survive in such kind of water?" asked Xu Yumei, a local fisherman in her 50s.
Xu said the fishermen had complained about water pollution to local authorities many times but it had never been solved, the paper reported.
"Even if we are able to find some fish, the fish smell so bad that they couldn't be sold," said Chen Qiaozhen, another fisherman.
The fishermen then turned to clear up garbage and dead pigs in the river to earn money.
The government also offered them an incentive - about 3,200 yuan annually to keep the river clean per kilometer.
The pay was higher than what they earned in fishing.
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