It's been more than a fortnight since the appearance of thousands of pig carcasses floating down the Huangpu River through Shanghai grabbed headlines across the country. Officials in China's largest city and in Jiaxing, the suspected source of the dead animals about 100km upstream, as well as the central government, have tried hard to calm the public by insisting there had been no major animal disease outbreak and that pork and water supplies were safe. But questions about the exact source of the carcasses and who should be responsible continue to be raised by the media. As of Tuesday, the Jiaxing city government had traced the source of 16 dead animals, from a sample of 17 pulled out of the river, from their ear tags and prosecuted their owners, People's Daily reported. However, neither Shanghai nor Jiaxing seem to have plans to trace the remainder, which at last count totalled more than 16,000. And, despite being the main pig-raising region for Shanghai, Jiaxing insists that is not the sole source of the carcasses. Jiaxing's explanation - that abnormally cold weather early in the year had made piglets, which constituted the bulk of the dead pigs, more prone to the common porcine circovirus, apparently failed to convince the media and the public. The Beijing Evening News said it was unreasonable for governments to be still giving ambiguous reasons for such a large number of dead pigs three weeks after the incident was first reported. "How could related departments not know anything about the death of so many pigs?" it said. Farmers in Jiaxing said that more dead hogs were dumped this year following a police crackdown on an illegal market for pigs that died on farms and were not legally slaughtered, which existed for many years. Shanghai's news portal eastday.com questioned the number of dead pigs the Jiaxing government claimed it had retrieved in its own streams. Jiaxing authorities announced on Friday that local workers recovered about 5,600 pig carcasses in rivers and lakes after a city-wide campaign to clean up the waterways. It said the clean-up effort officially ended on the same day. "It's apparently illogical for the source of the dead pigs to recover fewer pigs (than those found downstream in Shanghai)," the website said. Jiaxing's farmers raised about 7.5 million pigs last year, which would mean a premature death rate of about 200,000 just under normal conditions, it noted. Observers remain unconvinced by repeated assurances from Shanghai environmental authorities that water quality from the Huangpu, the source of one-fifth of the metropolis' drinking water, remained "normal" despite the presence of thousands of decomposing pigs. The Chongqing Morning Post argued that while residents were not unwilling to believe the government's monitoring results, they were sceptical that safety standards were sufficiently high enough and suspected certain tests may have been intentionally skipped. However, Shen Yiyun deputy head of the Shanghai water authority, told People's Daily he would drink the local water directly from the source if that's what it took to convince the public that it was safe. The governments of Jiaxing and Shanghai insist they have worked jointly to solve the problem, but there seems to be more talk than action. Their greatest co-operation probably lies in their publicity campaigns to smooth things over. While Shanghai officials repeated daily how many inspectors had been sent to check pork on sale and how closely river water and tap water were being monitored, Jiaxing launched a wide media campaign on how authorities had cracked down on the casual disposal of dead hogs in rivers. But the incident, at least in media's eyes, is far from over. A number of reports have appeared about pig carcasses in other rivers around the country.