Farmers received a further blow yesterday after Defra confirmed a case of avian flu at a farm on the Norfolk/Suffolk border.

Already reeling from recent outbreaks of foot and mouth disease and the bluetongue virus, farmers remained on high alert after birds on the premises, near Diss in Norfolk, tested positive for the H5 strain of the virus.

It is still not known whether the strain is the H5N1 virus which hit a Bernard Matthews farm in Suffolk in February this year, leading to the slaughter of 160,000 birds.

A three kilometre protection zone and a 10 kilometre surveillance zone have been set up around the site and all of the 6,500 turkeys, ducks and geese on the site will be slaughtered.