The mystery of big cats on the Mendips deepens as photographs have come to light which show an enormous cat taken at the time of a series of mysterious livestock killings last year.

Andrew Highfield, of West Pennard, photographed this big cat last year, but after failing to identify it thought no more of the matter.

However, after seeing reports in the local paper of sightings of a "wild cat", Mr. Highfield decided to share his picture.

Andrew said: "I showed the picture to a vet and he said it might be a Russian Blue or a Maine Coon. If you look at the picture, you can compare the cat to my cat – it's much bigger. And this picture was taken from 35 metres away or so!" Mr Highfield had seen the cat a number of times before and after the photograph was taken, often darting between houses at night or wondering into gardens during the day. This wild behaviour led him to believe it was not domesticated.

Max Blake of the Centre for Fortean Zoology said: "Though this is a very large cat, it's clearly a large breed of domestic cat, possibly a Maine Coon. Despite its unusual size, it is highly unlikely this cat is responsible for the sightings and killings last year."

This time last year, there were reports of a big cat in farms near Dulcote quarry slaughtering sheep.

Max attempted to track down the animals at the time.

Based on descriptions of the animal, along with the size and nature of its kills, Max suspected it of being a type of leopard, which fits the description of a cat which is black, low to the ground and with a curved end to its tail.

However, when he set up motion sensing cameras to try and catch the animal entering the farms, they were stolen and no pictures could be obtained.

Max said: "It's irritating to think that there could be some prole out there with a stunning photo of a big cat!"

Footprints, most of which turned out only to be those of a dog, and eyewitness testimony were the only pieces of evidence. As the year went on, the killings in the area stopped and the case went cold.

Recently there have been sightings of big cats in the area around Langport. Four weeks ago, Bob Underwood, 61, of Keinton Mandeville, saw a cat a similar size to a border collie dog.

Two weeks later, Emma Atkins of Langport saw a large feline cross the Langport Road.