Bird flu virus has been found on a second farm in US state of Delaware, state agriculture officials announced Tuesday.

The new case was discovered in a commercial flock of roaster-type chicken in the state's northern Sussex County, at least five miles (8 kilometers) away from the farm in southern Kent County where bird flu was first detected last week.

Following the latest finding, state authority has banned the sale of live poultry in Delaware. In addition, sales or auctions of farm equipment, meetings involving farmers and growers have all been canceled.

State officials said they will also kill 72,000 birds in three chicken houses on the Sussex County farm to stop further spread of the virus. The state destroyed 12,000 chickens after the first case was found.

The source and virus type of the second infection is not immediately known, though state agriculture officials confirmed that the virus found on the Kent County farm is a low-risk H7N2 strain, which has no harm to humans.

Flock on that farm was sold to the live bird markets in New York City and is believed to have contracted virus there.

With tests on 20 chicken houses within a two-mile (3.2 km) radius of the first infected farm being negative, the emergence of second bird virus case dealt a new blow to federal and state officials who are expecting bans on US poultry to be lifted soon.

"This development is completely unexpected given the precautions we took, the investigation we made and the industry's expectations of this disease's behavior," Michael Scuse, Delaware's Agriculture Secretary, said in a statement on Tuesday.

A growing number of countries have decided to temporarily ban imports of poultry products from the United States or Delaware alone. Delaware produces about 1.5 billion pounds of poultry annually, or about 4 percent of all US supplies.

(Xinhua News Agency February 11, 2004)