AROUND 28,000 birds are being culled in another suspected case of avian flu detected in Co Derry.
The birds belong to a commercial flock in Ballinderry.
Agriculture Minister Edwin Poots said on Tuesday this was the worst outbreak of avian flu across the UK.
Samples from the Ballinderry flock are being examined to confirm the presence of the highly pathogenic strain of avian influenza, which spreads rapidly and kills birds.
Four previous outbreaks have now been confirmed in commercial flocks in Aughnacloy, Coagh and Markethill, as well as a backyard flock in Broughshane.
Swans in Belfast’s Waterworks also had the virus.
Mr Poots urged flock owners to be vigilant.
“It’s extremely disappointing that this is now the worst outbreak ever across the UK and yet another stark reminder of the importance of excellent biosecurity measures which ultimately, are the only protection we have in preventing avian influenza getting into our housed flocks,” he said.
“This is a particularly persistent strain and it will use any lapse in biosecurity to gain access to a flock.”
The highly pathogenic avian influenza H5N1 has been discovered at various locations across the North of Ireland.
Birds that have been culled include a commercial flock of 22,100 ducks at Silver Hill Duck in Aughnacloy, and a hobby flock of 30 birds in Broughshane.
The strain has also been found in wild birds at West Belfast Lough, Monlough Lough in Carryduff, Hillsborough and the Loughshore in Portadown.