African swine fever has been documented in Bulgaria for the first time, after four pigs in a north-eastern town were determined to have died of the plague, an official said.
The State Agency for Food Safety said due to the outbreak of swine fever in neighbouring Romania, Bulgaria had begun erecting a 133-kilometre-long fence at the end of July.
Three more pigs are being held at the affected farm for observation.
In total, up to 27 pigs in the town of Tutrakantsi could be affected, reports said.
All pigs within a 3-kilometre protection zone around the town must be slaughtered per order of the food safety agency.
In addition, the trade and transport of pigs has also been banned in the region.
Farmers had tried to stop the slaughter of sheep and goats in the protection zone through protests.
Across Europe, more than 4,800 cases of African swine fever in both wild and domestic pigs have been reported so far this year, about 700 more than in 2017 in total.