A shocking video shows audiences running screaming from a circus in Russia after a trainer was attacked by a 600lb bear, Metro reports.

The brown bear had been taking part in the show in Olonets town, in the western Karelia region, where it was forced to push a wheelbarrow.

It then suddenly lunged at the circus worker, knocking him to the ground and biting his head and neck.

Those watching the show thought the attack was part of the performance at first, before they began screaming and scrambling for the exits.

They say there were no barriers between the bear and their seats.

In the footage, shouts can be heard as the bear starts attacking the trainer, causing the other performer to rush over and kick the animal.

The bear was then prodded with an electric shock device – but audience members said it still had time to move around in ‘a frenzied state’ before they felt safe.

It is believed the trainer was injured in the incident but no further information about his condition has been shared.