A Russian lake has mysteriously turned blood red in a transformation straight out of a horror film.

River

River

The body of water in the village of Gribanovsky - situation in south-western Russia's Voronezh Oblast region - suddenly turned a dark crimson, with authorities quickly alerted over fears whatever has caused it could contaminate the water supply.

As reported by the Daily Star, one eager social media user saw an opportunity and suggested it could be rented out to filmmakers looking for a creepy location to shoot a movie.

They wrote: ''Guys, you should use it as a financial opportunity. You should quickly get a contract for filming horror movies, and cash in while you can.''

According to local media reports, residents have now blamed a nearby sugary factory for the unusual change.

The reports add that the factory has been operating for 160 years - and in the past it's been linked to environmental issues.