A second herd of cattle on another farm in England has been culled because of foot and mouth disease.
The Department for Environment, Food and Rural Affairs (DEFRA) in Britain has confirmed that the herd of 102 cattle had been diagnosed with the clinical signs of the disease.
The farm is within the 3km protection zone around the first outbreak near Guildford, in Surrey.
According to senior veterinary officials samples from the second herd are being tested and local farmers have been asked to report any suspect cases so that the appropriate action can be taken swiftly.
The name of the second farm, has not been revealed but other farmers in the surveillance zone have expressed their dismay.
Investigators searching for the source of the initial outbreak are now said to be considering the possibility that flooding on the first farm may be to blame.
Wounds on the mouths of the infected cows suggest the disease was contracted between July 18 and 22, during which time it is reported there was a flood on the farm.
It has now emerged that cattle in the original outbreak had signs of the illness five days before the authorities were notified on July 29th; restrictions were imposed on Thursday, August 2nd, after the farmer alerted vets.
Dr. Debbie Reynolds, the government's chief veterinary officer says the investigation on the farm is taking all factors into account, including flooding, as the disease can be waterborne; it can also be carried through the air, or some other direct contact.
Experts say even if flood water were found to be the culprit, it would very likely have been a failure in treating effluent from the vaccine laboratories handling the foot and mouth virus at Pirbright, three miles away, which is presently the number one suspect in the case.
The Health and Safety Executive is shortly to release the findings of its preliminary investigation which appears to have pinned the source of the disease to Pirbright.
The Pirbright site is shared between the Institute for Animal Health, a government-funded research laboratory, and pharmaceutical company Merial Animal Health, whose work includes manufacturing animal vaccines; both say they have found no evidence of a breach in biosecurity.
Merial Animal Health has promised to temporarily restart production of a foot and mouth vaccine to deal with the strain of foot and mouth in the outbreak but the company's voluntary decision to suspend all production at its Pirbright centre remains for all other activities.
The EU has banned entry to all British exports of fresh meat, live animals and untreated milk products.
The Pirbright laboratories also conducts research into potentially fatal diseases such as CJD - the human form of mad cow disease, the highly dangerous variant Creutzfeldt-Jacob disease, avian flu, bluetongue, African horse sickness and salmonella in addition to foot-and-mouth disease.
Alarm has also been raised about the safety of government labs next-door to laboratories run by U.S.-based private companies such as Merial, and that biosecurity has been breached.
The safety of British science labs in the United States is also an issue, where the safety of their own local laboratories is under question because of the fears of a breach of biosecurity.
The two Pirbright labs have the same level of security as the germ warfare defence establishment at Porton Down on Salisbury Plain, Wiltshire.
The DEFRA Veterinary Laboratory Agency in Weybridge, Surrey, also carries out research on dangerous animal pathogens including work following the recent outbreak of bird flu and there are reported to be 36 other labs licensed to deal with dangerous pathogens.