Father and son went by snowmobile to inspect an ice hole for a future fishing trip. Stock picture

The boy - unnamed so far - obediently followed his father’s final command.

Vlasov had picked up the child from kindergarten before they went by snowmobile to inspect an ice hole for a future fishing trip.

Vlasov made the boy wait on the bank of the frozen Gur River while he turned the snowmobile - but the ice did not hold.

The man and his snowmobile crashed through the ice sank into the raging mountain waters.

Vlasov shouted in his final words: ‘Son, run to the store!’

The boy followed the tracks of his father’s snowmobile back towards the village of Kenay in Khabarovsk region.

Yevgeny Vlasov and his wife Maria.

But it was not an easy task.

He had to climb a 300 metre hill - in fierce cold.

Head of the village administration Yury Anekhov said: ‘The child saw his father sinking.

‘The boy later told me that his father shouted to him: 'Son, run to the store!'.

‘They have their own store in the village, and Yevgeny told him to go there.

‘The boy climbed a hillock, and then came down from it - its height is about 300 metres (985 ft).

‘Then he walked through the taiga.’

On his way he lost the track in the gloom.

By mistake he took a wrong turn.

But he was lucky.

Vlasov made the boy wait on the bank of the frozen Gur River.

A villager driving nearby saw the tiny figure trudging through the snow.

The man said: ‘He doesn’t speak too well yet - he’s too young - so he couldn’t tell me what happened.

‘I just understood that it was something really bad, and rushed to the village to find his family.’

The man said: ‘The little one was so smart.

'He had figured that the way back home was to follow the traces of his dad’s snowmobile.’

He reunited the boy with his mother Maria.

A day later the child succumbed to a ‘very strong fever’ but is otherwise not physically harmed from the traumatic experience.

Vlasov was a successful local businessman owning a chain of shops.

Local police chief Alexander Kolomytsev said that the chances of finding the body were slight.

It was a ‘fast mountain river’ and was impossible to use divers in the search.