GIANT 2ft South American "rats" are thought to be on the loose in Lincolnshire, according to wildlife specialists.

Snaps of a large long-tailed creature, which appeared to be a bloated rat, were taken by staff from pest control firm Rentokil Initial working at an unnamed factory in Lincolnshire.

But experts have said the animal – which has a huge furry body, long tail, pointed teeth and clawed feet – is much more likely to be a coypu, a type of rodent indigenous to South America.

Field biologist Claire Hewitt, 37, of Universal Pest Control in Bracebridge Heath, said: "Although the picture isn't completely clear, it does appear to be a coypu.

"The main difference is in the size of the body and the blunted nose. Rats tend to have longer snouts and their hind legs are also smaller."

Although its appearance could send a shiver up your spine, the rodent differs from meat-eating rats because it is a herbivore. It tends to burrow near stretches of water and feed on river plants.

The animals have been known to breed rapidly in the wild and can quickly cause heavy damage to riverbanks with their burrowing. Efforts to stamp them out in Norfolk have been ongoing since the 1930s.

"They are sometimes called a swamp beaver because of how much they resemble them and they are related to the porcupine," added Miss Hewitt.

"They are a rodent but, unless they become a public health issue, they can be left alone."

Malcolm Padley from Rentokil Initial said: "Rodents like any other creatures can grow large in the right conditions. Any rodent sighting whatever size should be taken seriously."