SOFIA (Reuters) – An outbreak of a virulent bird flu virus has spread to a farm in southern Bulgaria, the Balkan country’s food safety agency said on Friday.

A three-kilometer protection zone was set around the farm in the village of Trilistnik, near Bulgaria’s second-largest city of Plovdiv and the sale of eggs and the movement of domestic, wild and other birds was banned within it, the agency said in a statement.

The agency said that all contaminated 43,000 hens at the farm would be culled in a humane manner.

(Reporting by Angel Krasimirov; editing by Emelia Sithole-Matarise)