The Russian Navy has defended the shooting of a mother bear and its cub on a nuclear submarine following outrage among many social media users.

The Navy says there was no other option after the animals climbed onto the vessel moored off the Vilyuchinsk base in the far-eastern Kamchatka region.

It says a hunting instructor was called in to "neutralise the wild animals".

Hundreds of social media users accused the Navy of unnecessary cruelty after seeing a video of the shooting online.

"Animals!" and "The whole essence of Russia in one video" were some of the comments.

The footage was published on 8 November, although it is unclear when the shooting happened.

Mother bear and cub shot after climbing onto Russian nuclear submarine https://t.co/MAXpZ45O2n

— BBC News (World) (@BBCWorld) November 9, 2020

In the video, one of the animals is seen falling into the water after apparently being hit by a bullet.

A male voice in the video is heard saying the animals would have gone to local villages had they been driven away.

The bears, whose species was not disclosed, are believed to have swum across the bay to get onto the submarine for reasons unknown.

The Kamchatka peninsula is home to about 24,000 bears that can frequently be seen on local beaches.

Last year, more than 50 polar bears descended on a village in Russia's far north.

All public activities in Ryrkaypiy, Chukotka region, had to be cancelled, and schools were guarded to protect residents from the animals.

Conservationists say climate change could be to blame, with weak coastal ice forcing the bears to search for food inland rather than at sea.