German authorities started culling tens of thousands of birds at two farms in the Bavarian towns of Trumling and Hofing as a protective measure over fears of the deadly H5N1 strain of bird flu.

An outbreak of bird flu was identified in the nearby Bavarian town of Wachenroth on Aug. 25 after dead ducks found in a poultry farm tested positive for the highly pathogenic H5N1 strain of the virus.

Frank Pfeffer, a spokesman for the state office in Schwandorf, said 205,000 birds will be culled in a drive that is expected to run into next week.

The farm in Wachenroth in Bavaria's Erlangen-Hoechstadt area was sealed off and all 160,000 birds there were culled. Officials discovered the infection after more than 400 ducks at the farm died over a short period of time.

The two farms in Trumling and Hofing had business ties with the farm in Wachenroth. Tests conducted on the birds in Trumling and Hofing found that they had antibodies that indicated the presence of H5N1, Mr. Pfeffer said.

He said there was no outbreak of bird flu in Trumling or Hofing and that none of the birds showed signs of illness. But he added the blood tests were enough to justify the culling action.

Germany identified several cases of the deadly H5N1 strain in wild birds in Bavaria in June. Several bird flu infections were also registered in Germany last year.

Globally, the H5N1 virus has killed 195 people out of 322 known cases, according to the World Health Organization. Hundreds of millions of birds have died or been slaughtered.

The vast majority of bird flu deaths have been in Asia. No deaths have yet been registered in the European Union. deaths have been registered in the European Union.