A report released yesterday by the Institute for Animal Health (IAH) concluded that the two outbreaks, one in the Pirbright lab site in Surrey and the second only 11 miles away, came from the same source, suggesting the first was therefore not eradicated.

"The September infected premises were located outside of the original 10km surveillance zone and therefore could not have been picked up by the extensive surveillance and sampling we carried out," said a spokesperson for Defra.

For this reason, Defra said the agricultural industry also has a role to play in preventing or containing such outbreaks by remaining alert.

Researchers at the IAH studied the genetic fingerprints of the foot and mouth virus recovered from the different premises in the outbreak and found that they comprised a single chain of transmission events. They said they have actually determined the probable sequence of transmission.

Commenting on the research techniques used, Defra spokesperson said: "Important to note is that this genetic sequencing is a new technique. We are still developing our understanding of how to interpret this data but it suggests infection moved from the August infected premises direct to the September infected premises."

The information, which was passed onto Defra in September, has now been published in response to media suggestions that the second phase of the infection in the Virginia Water area was caused by infected soil removed from land housing the IAH's Pirbright laboratory and the vaccine company Merial.

The IAH and its sponsoring body, the Biotechnology and Biological Sciences Research Council strongly refute those claims.

Defra said there were no attempts to conceal the research. It said: "There has been no suppression of this data. Defra gave IAH permission to publish this data on 5 October."

The data was peer reviewed by a group of leading scientists at the request of Defra's Chief Scientific Adviser and are due to published shortly.

The independent expert peer review process has accepted the study's conclusions that the second phase of the outbreak originated from the first phase and not from a separate release.

The damning report comes on the same day the Callaghan review was released, stripping of its role as regulator of laboratories handling animal pathogens.

Sir Bill Callaghan's review, commissioned by the secretary of state Hilary Ben, recommends a three-phased approach to implement changes to strengthen regulatory framework for the handling of animal pathogens.

Responsibility will now pass to the Health and Safety Executive, which will deal with both animal and human pathogens.

Hilary Benn, said: "I agree that Defra should not continue as regulator of laboratories handling of animal pathogens. This is because of the clear need to have a single independent regulatory body."