German authorities said on Sunday that they had finished culling 30,000 domestic birds in the area where the first bird flu case on a commercial poultry farm was found.

A spokesman for the state of Saxony said a commercial poultry farm in the town of Wermsdorf and a slaughterhouse nearby would be thoroughly cleansed to rid them of any traces of H5N1 bird flu virus.

Scientists at the Friedrich Loeffler Institute of animal health confirmed on Wednesday that the H5N1 strain of avian flu virus had been found on the farm. However, they added that further tests were being carried out to see if it is the highly pathogenic Asian variety, which has killed more than 20 people this year.

An exclusion zone has been set up covering a radius of three kilometers around the infected site, and an observation area of a 10-kilometer radius has been established.

This has been the first case of bird flu at a commercial poultry farm in Germany, where hundreds of wild birds and three domestic cats have died of the virus since it was discovered in early February.

The virus was first detected in the country among wild birds on the island of Ruegen in the Baltic Sea, but it has since rapidly spread to seven states.

The German government announced at the end of last month that it would spend 60 million euros (73 million U.S. dollars) on bird flu research in the next four years, hoping to develop a vaccine for humans soon.

The H5N1 strain has killed more than 100 people globally.