The Ministry of Agriculture has launched an urgent investigation into the deaths of more than 5,000 pigs whose carcasses ended up in East China's Huangpu River.

The probe will also involve animal epidemic protection departments in Shanghai and Zhejiang province, said Chen Xiaohua, vice-minister of agriculture.

Officials first started receiving calls about dead pigs in the upper Songjiang section of the river last week.

By Tuesday, 5,916 carcasses had been retrieved, according to Chinese news portal .

Initial investigations have found no evidence of widespread animal disease in the immediate area, Chen said on Monday, although tests have revealed some pigs may have died from porcine circovirus, a disease common in pigs in recent years.

Shanghai authorities said that from the animals' ear tags they have so far determined the pigs came from Jiaxing in Zhejiang province.

Shanghai's Agriculture Committee said it has been in contact with animal departments in Zhejiang and the agriculture department of Jiaxing, and has sent officials to ask local departments to take appropriate measures.

滬江英語(yǔ)：截至3月12日15時(shí)，上海市已累計(jì)出動(dòng)打撈船只233艘，共打撈死豬5916頭。目前打撈量已開(kāi)始下降。上海繼續(xù)加強(qiáng)與浙江省和嘉興市農(nóng)業(yè)部門(mén)的聯(lián)防聯(lián)控，從源頭上落實(shí)防范措施。3月12日上午9點(diǎn)30分，嘉興市政府召開(kāi)媒體見(jiàn)面會(huì)，通報(bào)死豬事件相關(guān)情況。嘉興市畜牧獸醫(yī)局副局長(zhǎng)蔣皓在會(huì)上表示，嘉興方面已經(jīng)收到上海送來(lái)的14個(gè)豬的耳標(biāo)，經(jīng)確認(rèn)耳標(biāo)都屬于嘉興地區(qū)。但他也強(qiáng)調(diào)，耳標(biāo)并不能判斷養(yǎng)殖地一定在嘉興。