ULAN BATOR, Jan. 21 (Xinhua) -- The Mongolian authorities on Monday said the East Asian country has beefed up its fight against an outbreak of African swine fever.

Since the first case of the viral disease in pigs was recorded earlier this month, some 1,500 pigs have been slaughtered, Mongolia's General Agency for Specialized Investigation said in a statement.

As of Monday, there have been case reports in the capital Ulan Bator and more provinces recently. The provinces now include Khuvsgul, Bulgan, Orkhon, Selenge and Darkhan-Uul in the north, Dundgovi in the south and Tuv in central Mongolia, it said.

The agency said its officials have carried out inspection tours in the affected areas and seized infected pork from markets and restaurants.

Transport of all pigs and related products out of and into the listed places has been banned, and the country has suspended the import of pork products from the countries affected by the African swine plague, it said.

African swine fever is a highly contagious, lethal disease believed to infect swine only. No humans nor other species have thus far been found infected.