Karachi, Feb. 28 (Reuters): Pakistani authorities culled thousands of chickens today at two farms where a mild form of bird flu had been detected, and officials awaited results from tests on whether the strain found could pose a danger to people.

“The step had been taken as a precaution and all the birds have been destroyed,” Livestock commissioner Muhammad Afzal said, commenting on a cull of around 23,000 chickens at the farms in two cities in North West Frontier Province.

“We don’t want the outbreak to spread,” he said. “There is no report of flu from any other farm in the country,” he added. Initial tests in Pakistan pointed to the presence of the H5 subtype virus at the two farms.

Samples of the infected birds were being sent to laboratories in Britain to check whether they had contracted the deadly H5N1 virus that has wrought havoc among poultry flocks in much of Asia.

“We are also conducting tests locally but it will take three weeks for us to complete these tests,” Afzal said. “It’s better to take an international opinion as well, so we have sent the samples to Britain.”