Four trained bears with a touring circus went into hibernation during a road trip to a venue in the Russian Far East, a trainer said on Monday.

"Four female bears, Varya, Manyasha, Lyalya and Lyusya, were traveling in a huge truck from Irkutsk to Vladivostok," Vladimir Dobryakov told RIA Novosti.

"It took us eight days to cover the distance of 4,500 kilometers, which was, of course, a lot of strain for the animals," he went on, adding that the truck broke down on the way.

The situation was further aggravated by extremely low temperatures, which forced Dobryakov to give the dormant bears large quantities of strong tea and chocolate candies so as to stop them from falling asleep.

Bears are common in Russian circuses. Some are trained to skate on ice and play hockey.

VLADIVOSTOK, December 20 (RIA Novosti)