Hong Kong health authorities have confirmed that the recent outbreak of bird flu in the area was caused by the highly pathogenic H5N1 strain.

Chickens were first found on a farm in the Yuen Long district. Tests confirmed the birds had bird flu, and consequently 80,000 birds were culled. Additonally, imports were halted for 21 days.

Bird flu source

Reports state that some chicken traders believe that fertilized eggs smuggled from mainland China may have started the spread of the disease.

"We aren't ruling out any possibilities, though the H5N1 source is not likely to have come from inside the farm but to have come from outside," said Health Secretary York Chow.