A Bluetongue control zone has been imposed over a wider area of north Suffolk and south Norfolk as more cases come to light.
A 20km temporary control zone (TCZ) was declared on Bank Holiday Monday after the disease was found in a sheep.
Three new cases discovered yesterday near Lowestoft and Norwich have resulted in temporary restrictions on the movement of livestock being extended.
All three animals will be humanely culled to minimise the risk of onward transmission, said the Department for Environment, Food and Rural Affairs (DEFRA).
The zone now includes Halesworth and Southwold in Suffolk and Norwich, Attleborough, Dereham, Long Stratton and Reepham in Norfolk.
The disease - carried by midges - can have mild to severe effects on livestock but does not affect humans.
The first case this vector season turned up in a single sheep on a mixed farm near Haddiscoe in South Norfolk on Monday.
Norfolk bluetongue serotype 3 (BTV-3) has now been confirmed in the animal.
The movement restrictions apply to cattle, sheep, other ruminants and their germinal products (semen, ova and embryos).
The latest development adds to the stress being felt by livestock farmers in the region.
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