A cow in Watford has tested positive for the potentially deadly disease bluetongue, the government has tonight (Friday) announced.

It is unclear where the cow is from, however, a 20 mile protection zone, which extends across Hertfordshire as well as into London and Buckinghamshire, has already been set up around the town.

The Department for Environment, Food and Rural Affairs (Defra) has said there are now 75 confirmed cases of the virus, which is spread by midges and can be fatal to animals such as sheep and cows.

It is believed the cow tested positive following routine testing.