A United Nations official says North Korea has contained its bird flu outbreak, but is not yet free from the disease.

Les Sims, a consultant to the Food and Agriculture Organization, visited the North for an inspection earlier this month.

Speaking on Voice of America Wednesday, he said the North acted promptly and appropriately on the outbreak, but wondered how bird flu broke out since chicken farms there are well run.

He urged the North to better detect poultry disease.

Last month, the North confirmed outbreaks of bird flu in three major poultry farms, including one close to Pyongyang.

Authorities there said they culled over 200 thousand birds and vaccinated poultry in unaffected areas.