A farm on the Surrey-Sussex border is being investigated for foot-and-mouth disease.

The Ministry of Agriculture has closed down Whiteleaf Farm in Smallfield, near Horley, after a possible outbreak in a herd of sheep.

Today a sign on the farm gate says: "Foot and mouth. Please keep out. These premises are under observation."

Sussex farmers are on the alert and say the spread of the disease into the county would be devastating.

Annie Payne, secretary of the NFU Mid Sussex group, said the Horley farm was being investigated because of a "dangerous contact". It bought animals from another farm which either has the disease or is being investigated.

She said: "Sussex has been very lucky to escape until now. All the farmers are on tenterhooks."

NFU regional director Shaun Leavey, said: "I believe that the person involved in this investigation is a dealer, so we can assume there has been a fair amount of livestock movement.

"However there have been many farms which have been served notices but found to be disease-free. It may take up to a week before we know one way or another."

The Government has already announced plans to slaughter 300,000 healthy sheep in a bid to halt the spread of the disease.

Yesterday there were nine new cases of foot-and-mouth, taking the number of confirmed cases in Britain to 334.

In Devon, troops have been sent in to help dispose of the carcasses of slaughtered animals.

But many farmers feel not has been done over the last four weeks to stop the disease from spreading.

Tim Carnaghan, of Standean Farm in Patcham, Brighton, said: "I think initially farmers in this area were almost a little bit complacent. It started so far away. When it moved into Kent we woke up.

"Now people are very concerned because it certainly doesn't appear to be under control in any sense of the word. It needed to be hit as hard as possible. If this outbreak is confirmed it just 20 miles from here.

"We are already limiting the movements of our livestock on and off the farm. We haven't sent any livestock to the slaughterhouse as we are worried about having any vehicles, even disinfected ones, on our land. An outbreak of foot and mouth in Sussex would be devastating."

A spokeman for Surrey County Council said there was no reason to panic and the farm in Smallfield was being investigated as a precautionary measure.

He said 30 sheep had been returned to the farm from a collection centre in Canterbury where an outbreak was later confirmed.

Councillors from across Britain have voted to ask the Government to delay the county council and general elections because of the crisis.

Meanwhile Drusillas Zoo Park at Alfriston, near Polegate, is to reopen.

It closed in response to the foot-and-mouth outbreak on February 28 and will reopen on Friday.