An upcoming documentary which is investigating animal sightings in Britain has reported that DNA evidence has been found that matches that of a big cat.

'Panthera Britannia' is a documentary being produced by Dragonfly Films, looking into the existence of big cats in British countryside.

In a recent development DNA has been found matching a big cat at the scene of a sheep attack at a farm in Gloucestershire.

The black hair caught on a barbed wire fence has offered "definitive proof" big cats are roaming the British countryside after the strand was sent off for testing.

The farm had previously seen "unusual predatory" activity, with video footage of a large black animal also captured only a few miles away from where the sample was taken.

A forensic laboratory took on the species identification task and used mitochondrial DNA analysis to ascertain a 99 per cent match to a big cat species.

Matthew Everett, from Dragonfly Films, said: "It’s taken five years for the production team to find such evidence and film its journey from collection to analysis.

"People in Gloucestershire and Britain have described what appear to be black leopards for decades. So, a leopard DNA result from a black hair sample is unsurprising.

"This is not the first such DNA result and is unlikely to be the last.

"There is a great deal of ‘secondary evidence’ for these cats, such as consistent witness reports, but hard evidence like DNA is hard to get, so the contribution from this documentary is very helpful.

"Collecting such evidence from local people, farmers and landowners is essential - Citizen Science like this will hopefully help us learn more about the Bagheera type big cats which may be quietly naturalising here."

In Berkshire, motorists have been reporting large cats around the M4 for years.

Lorry driver Joe Ashford was driving on the M4 on January 25, southeast of Reading when he says he saw what he describes as a 'large cat'.

He described the animal as a "small leopard with hyena-like colours".

A second person also reported a sighting on the same stretch of road.

Isaac Latchman said: "I’ve seen the same big cat in the woodland areas between Junction 11 and 12 on the M4. 

"I’ve seen it early morning on two occasions.

"I thought it may be owned by a private keeper but I’m unsure - there is definitely a huge cat roaming near Reading with cougar-like colours."

The Reading Chronicle previously spoke to Associate Professor of Ecology and Evolutionary Biology at the University of Reading, Dr Manuela González-Suárez who did not rule out the possibility of big cats roaming wild in the area.

She said: "It is possible that somebody had a big cat as a pet and that that animal might have escaped."

However, she added: "I don't think an animal could last on its own without being clearly identified and tracked down in an area like Berkshire for very long."

Dragonfly Films is currently pursuing broadcast options for Panthera Britannia Declassified. An earlier version of the film “Panthera Britannia” is available on Amazon Prime, Vimeo and Apple TV.