A mass die-off of bees has been reported in the Russian Urals region of Chelyabinsk, with the causes under investigation, according to the local veterinary service. Millions of bees have also reportedly died in Siberia's Krasnoyarsk Region districts, with no infectious or parasitic diseases detected in them, the regional veterinary service said. Chelyabinsk Region- More than five million bees died in a district of the Chelyabinsk Region, while the causes are still unknown, an official at local veterinary service told TASS. - Earlier, the media reported that about 30 million bees died in one of the region's districts because of the use of potent pesticides in neighboring fields. - No infectious or parasitic diseases were detected in the bees, according to the regional veterinary service.