After two mysterious cats were spotted by a camera in the Sundarbans, forest department officials are now tracking the movement of the animal to find out if it is the never-before-seen melanistic leopard cat. During a camera trapping exercise by WWF-India to estimate the population of tigers in South 24-Parganas forest division, images of two black cats with long tails were found for the first time a few months ago.

S B Mondal, principal chief conservator of forests (PCCF-wildlife), said efforts were on to trace the animal and unfold the mystery.

He told PTI that they had written to the Union Ministry of Environment and Forest seeking permission to trap the feline species for a genetic testing.

"The testing will prove our belief that it is a melanistic leopard cat. It is significant because such a cat has never been reported from any where else in the world," said WWF's Anurag Danda.

The cat spotted in the camera traps is bigger than a wild cat and smaller than a leopard.

Melanism is the undue development of dark-coloured pigment in the skin which gives black skin in many animals, birds and even fishes. Black panther is the best known example of melanistic cat.