Alexey Volkov, 25, was left reeling when he caught two sinister “underwater dragons” with a frightening faces, sharp teeth and multiple horns.

The angler, who caught the bizarre pike from Siberia’s River Irtysh was bemused by the apparently mutated creatures.

Volkov has no idea why the pike, which were pulled from the river last autumn, sprouted monstrous horns on the tops of their heads.

But one theory put forward by locals suggests radioactive debris from space rockets launched at Baikonur Cosmodrome in neighbouring Kazakhstan could be to blame.

“I was impressed with the catch,” said Volkov, from Tara, a small town in Omsk Oblast, Russia

“The fish were 14kg and 7kg.

“They had horns bent back towards their tail.

“The smaller fish had four horns."

Locals fear that pollution – possibly radioactive – was behind the weird fish in the Irtysh, a popular pike river for anglers.

Baikonur Cosmodrome, the world's first and largest operational space launch facility, is currently being leased to Russia by the Kazakh Government until 2050.

Under leader Vladimir Putin, Russia’s space programme regularly launches commercial, military, and scientific missions from Baikonur, in the desert steppe of Baikonur.

Against the advice of pals, Volkov ate the potentially radioactive pike – but did not experience any negative health effects.

He preserved and dried the heads of the fish, which he keeps in his garage.

For years there have been concern over the impact of launch-stage rocket debris in Omsk region.Local reports have questioned whether this is behind illnesses in babies.

A zirconium plant – now disused – is also close to the place where the fish were landed.

Expert Arkady Balushkin, chief of the Ichthyology laboratory of the Russian Academy of Sciences Zoological Institute, was sceptical about pollution as the cause.

“Any change happening under influence of chemical substances or radiation does not lead to new formations like this,” he said.

“A pike would still remain a pike.

“It might develop a tumour or oedema, and these are typical illnesses for these species.

“But it is not supposed to have any horns.

“To confirm that it was a pike with horns, and not another fish, I would need to see it for myself.”

Another claim is that this could be a fish-version of cutaneous horns, which on rare occasions grow on humans.

Horned pike often appear in ancient folklore tales told in the region.

An article by Dr E J Crossman, highlighted by the Pike Anglers’ Club of Great Britain, also suggests the phenomenon in this type of fish, while, exceptionally rare, is not unknown.

He wrote in 1987: “In moments of excitement I think many Pike anglers have compared the personality of the Pike to that of one of the more infamous, mythical or real, horned beasts.

“The same anglers would not, however, expect to actually find horns on their quarry once it was landed. Nevertheless in six isolated cases to date that is exactly what has happened.

“All six fish had very obvious structures referred to as ‘horns, spines or prongs’.”

A similarly bizzare mutant-looking black fish was caught in Russia's Udmurt Republic by fishermen in 2016.