Some beef products have been removed from shops after a Northern Ireland meat company was found to have breached BSE testing regulations.
Liver, steak and mince have been removed from some shops
Asda and the Co-op are recalling liver, steak and mince products supplied by Dunbia Northern Ireland, formerly known as Dungannon Meats.
A Food Standards Agency spokesman said the company "slaughtered an old cow without the proper tests".
He added, however, that the risk to consumers was "extremely low".
Morris McAllister said the agency was concerned about the "breakdown in procedures".
"We are working with the Department of Agriculture and the company concerned to find out exactly what did happen and to put procedures in place to prevent it happening again," he said.
"We feel that consumers have a right to know what has happened and also it's our responsibility to protect consumers, so we are having the material removed from the shelves."
ASDA said in a statement that Dunbia only supplied its beef liver and the supermarket's other meat products were unaffected.
Northern Ireland beef returned to the European market when the ban was lifted earlier this year.
Live cattle born after 1 August, 1996 can now be exported, as can beef from cattle slaughtered after 15 June, 2005.
Restrictions remain for beef containing vertebral material and for beef sold on the bone.
European officials agreed to lift the ban as cases of BSE dropped in the UK.