A strain of the bird flu virus that can spread to humans has been found among poultry in northern Nigeria.
The Paris-based World Organization for Animal Health says it found a "highly pathogenic" version of the H5N1 strain at a chicken farm in the village of Jaji in Kaduna state.
This is the first reported case of H5N1 in Africa.
The organization says Nigerian authorities have disinfected the premises, and imposed a quarantine and restrictions on the movement of animals.
It says it plans to coordinate a joint response to the situation with the U.N.'s Food and Agriculture Organization.
Avian flu has killed or forced the slaughter of millions of birds over the last two years. The H5N1 strain has killed at least 88 people in seven countries, mostly in Asia, since late 2003.
Some information for this report was provided by AP and Reuters.
