Chinese authorities have launched an investigation into whether government officials dined on pangolin, the world’s most trafficked mammal, at a banquet in Guangxi province in 2015.

The investigation was prompted by a resurgence of social media interest in a series of photographs of the meal, first published in 2015. The photos were posted by Weibo user Ah_cal, who claimed the banquet had been hosted by Chinese government officials. One of the dishes shown was a pot of meat, which Ah_cal described as “cooked pangolin.”

The pangolin meat was “delicious,” the Weibo user wrote in a caption, noting that the mammal was a particular culinary favorite of one of the officials hosting the event.

Chinese news outlets have identified the Weibo user as a Hong Kong businessman. He has since deleted the photographs.

“These days the quality that stands out most in our officials is wickedness,” said one Weibo user, according to Agency-France Presse.

Chinese forestry officials said on Wednesday that they’d launched an investigation into the incident.

Government officials from the Guangxi Investment Promotion Bureau have been fingered as the possible hosts of the banquet, reports Chinese news agency Xinhua. The bureau, however, has denied any involvement.

“We have diligently identified the diners in the photographs, and none of them belong to Guangxi Investment Promotion Bureau’s leadership or staff,” a spokesperson told newspaper Chengdu Shangbao.

A regional disciplinary commission has supported this claim. The commission told Xinhua that the bureau had indeed hosted an investment tour for Hong Kong entrepreneurs in July 2015, but the banquet — which it described as a “private” event — had happened after the tour and involved a few “individual members of the group.”

A government official was at the banquet, the commission said, but it was a man named Li Ning, a former official with the regional work committee of higher education. Li was arrested in May 2016 on suspicion of corruption, Xinhua reports.

Getty Images This pangolin was released into the wild after being seized from the illegal trade in Sibolangit, North Sumatra, Indonesia on April 27, 2015.

The primary threat facing pangolins is poaching. At least 10,000 pangolins are killed every year, both for their scales and their meat. Pangolin scales are highly-prized in Chinese traditional medicine (they are made of keratin, the same material as human fingernails, and have no medicinal value) and their meat is considered a delicacy in some parts of Asia.

Paul Hilton/Wildlife Photographer of the Year Awards Photographer Paul Hilton captured this photograph last year of thousands of frozen pangolins that had been seized from a seafood trading company in Indonesia. This photograph won first prize in the single image category at the Wildlife Photographer of the Year awards in October.

In September, the Convention on International Trade in Endangered Species of Wild Fauna and Flora, or CITES, banned the international trade of pangolins and their parts. A few months later, Chinese authorities announced the largest ever seizure of trafficked pangolin scales in the country. More than three tons had arrived in a Shanghai port from Nigeria. Approximately 5,000 to 7,500 pangolins were estimated to have been killed for that shipment.

In China, the pangolin is a protected animal. Eating its meat is punishable by up to 10 years in prison, according to the AFP.