A family last night spoke of their devastation after bird flu decimated their flock.

The past 24 hours have been a nightmare for the Court family, culminating yesterday with the slaughter of their flock of 25,000 hens.

At the same time Defra announced laboratory results from dead chickens confirmed the outbreak of the highly contagious H7 strain of bird flu.

Jonathon Court said the family had run Eastwood Farm, between Shenington and Shutford, near Banbury, for more than 50 years and the free range poultry unit for five years.

Mr Court said an increase in bird deaths had prompted them to call in a vet.

After monitoring the situation Defra was informed and carried out tests.

He said: "The source of the disease is not yet known and Defra will continue to make further investigations to try to identify this. All birds on the farm will be culled to try to help contain or eradicate the disease.

"We would urge everyone within the Defra surveillance zone to remain vigilant and to maintain suitable bio-security measures on their farms. This has been a devastating 24 hours for us and we would ask that we are now left to come to terms with what has happened and make plans for the future."

A 10km surveillance zone was placed around the farm banning all bird movement to prevent the spread of the disease.

Over the next few days Defra vets will visit all farms and small holdings within a 3km protection zone to test animals.

Yesterday teams of Defra staff arrived with equipment, and specialist vets carried out the slaughter.

Last night carcases were taken in sealed lorries to an incineration plant.

Local farmers have been seeking support and advice from the National Farmers' Union.

Spokesman Mike Wynn said: "It's still early days in terms of being able to know quite where this has come from, and Defra are there carrying out tests."

The family will be compensated by the Government for the slaughtered chickens and once the farm has been given the all-clear they can start to rebuild their flock.

The Health Protection Agency has confirmed that the risk to public health remains low and the Food Standards Agency also confirmed there are no safety implications for the human food chain.

Poultry keepers are urged to be extremely vigilant, practice the highest levels of biosecurity and report any suspicions of disease to their local Animal Health Office immediately.