LONDON - Britain's farm ministry on Tuesday reported a third case of bluetongue disease in an animal in Suffolk in eastern England.

The Department for Environment, Food and Rural Affairs (DEFRA) said an animal had tested positive in a premises near Lowestoft, Suffolk.

Britain's first ever case of bluetongue was reported on Saturday in Baylham, also in Suffolk, and a second case was reported at the same farm on Monday.

Baylham and Lowestoft are about 45 miles (72 km) apart.

"This announcement is obviously worrying but not unexpected following the large number of bluetongue cases there have been in northern Europe," Pamela Forbes, regional director of the National Farmers Union, said in a statement.

The ministry said there was still not yet sufficient evidence to confirm an active outbreak of bluetongue as it could not yet be demonstrated the disease was circulating and the cases were not the result of a single incursion of infected midges from abroad.

"A bluetongue outbreak would be difficult to deal with but farmers will be hoping that the disease can be contained with measures such as animal movement controls and insecticide treatment of places where midges are likely to congregate," Forbes said.

Bluetongue causes fever and mouth ulcers and in some cases turns an animal's tongue blue. It is transmitted by insects such as midges and can be highly dangerous to sheep and cows, although it does not affect humans.

The disease is mostly found in Mediterranean countries such as Italy, Spain and in North Africa, but has spread this year across five more northerly EU countries -- Belgium, France, Germany, Luxembourg and the Netherlands.