MOSCOW, February 22 (RIA Novosti) - Laboratory tests have confirmed the deadly avian flu virus in culled birds in three more districts in the Moscow Region, bringing the total number of affected districts to eight, the local agriculture and food ministry said Thursday.

The ministry said the virus has now also been confirmed in the Volokolamsk, Ramenskoye and Odintsovo districts.

Cases of avian flu have already been registered in the Odintsovo, Domodedovo, Podolsk, Naro-Fominsk and Taldom Districts, all of which were traced to a single market in southwest Moscow.

No cases of humans infected with the virus have been registered so far.

Moscow's veterinary and food safety experts have urged local residents to avoid buying poultry at unauthorized locations, and prosecutors have launched a probe into "veterinary violations."

According to the World Health Organization, the deadly H5N1 strain of bird flu has claimed 167 human lives globally since it first appeared in Asia in 2003. It has since spread worldwide, and scientists fear the virus could mutate into a form transmissible between humans, sparking a global pandemic.

Russia recorded its first cases of avian flu in August 2005, but until now outbreaks have occurred only in southern provinces and in Siberia.