By Nigel Hunt LONDON (Reuters) -Bird flu has been detected in a sheep in northern England, the first known case of its kind in the world, Britain's government said, adding to the growing list of mammals infected by the disease and fuelling fears of a pandemic.

This is the first time that the avian flu virus has been reported in a sheep, but it has been detected in livestock in other countries. Despite this, there is no evidence to suggest that an increased risk to the UK’s livestock population exists.

The H5N1 virus was detected in a single sheep in Yorkshire, England, during routine testing conducted on a site where avian influenza had previously been identified in birds. No other sheep in the flock tested positive for the virus.