Where did the outbreak of bird flu start?

Russia, which is scrambling to contain a bird flu outbreak in Siberia, warned the world on Monday that migrating birds may export the deadly virus to Europe and the Middle East in coming months. The outbreak, previously confined to five remote areas of Siberia, appeared to be moving westward on Monday after the virus hit a major industrial region--Chelyabinsk in the Ural mountains which sever Asia from Europe.
     And officials said the virus, which can kill humans, was likely to spread further. Media reported that roads leading to the infected village of Oktyabrskoye in Chelyabinsk had been cordoned off to prevent the virus from spreading further. In other affected regions, police boosted road checks, and 400 domestic birds were culled in Chelyabinsk alone to block the virus that has killed more than 10,000 birds countrywide.