TOKYO (Reuters) – Japan found African swine fever in packed pork sausage being carried into the country by a foreigner coming from Beijing early this month, the nation’s agriculture ministry said on Tuesday.

The incident comes amid growing concerns over the spread of the deadly infection in Asia. China has reported more than 40 separate outbreaks of the disease in 11 provinces and municipalities since discovering its first case in August, leading to the culling of around 200,000 animals. The sausage was collected from a foreigner arriving at New Chitose Airport in Hokkaido, northern Japan, on Oct. 1. Genetic testing at an animal quarantine station detected the disease in samples of the product last Friday, according the ministry.

Bringing pork meat and pork products from China is prohibited in Japan. The sausage came in a vacuum pack and had apparently been heat treated, suggesting there is little chance of it being infectious, an official at the ministry said.

But the ministry is still investigating the case further at a research institution in Tokyo, the official said.

It was not clear where the sausage was made, he said.

There were two similar cases where African swine fever was found in livestock products brought by travelers from China in South Korea, the ministry said.

After the first outbreak of the disease in China, Japan tightened quarantine operations at airports and seaports, especially for travelers from areas where the infection has been found. Since last Friday, Beijing has been added to the list of the targeted areas, the official said.

(Reporting by Yuka Obayashi; Editing by Tom Hogue)