Tesco have taken out full-page adverts in several national newspapers to apologise to customers after horsemeat was found in some beef burgers.
The advert reads:
"You have probably read or heard that we have has a serious problem with three frozen beef burger products that we sell in stores in the UK and Ireland.
"The Food Standards Agency of Ireland (FSAI) has told us that a number of products they have recently tested from one of our suppliers contained horsemeat.
"While the FSAI has said that the products pose no risk to public health, we appreciate that, like us, customers will find this absolutely unacceptable.
"We have immediately withdrawn from sale the products from the supplier in question, from all our stores and online.
"If you have any of these products at home, you can take them back to any of our stores at any time and get a full refund. You will not need a receipt and you can bring just back the packaging.
"We and our supplier have let you down and we apologise.
"So here' our promise. We will find out exactly what happened and when we do, we'll come back and tell you."
The horsemeat scandal demonstrates how long and complicated the food chain we all depend on is. Regulating our food supply is expensive.
Some of the best, and worst, jokes and gags from Twitter users discussing the discovery of horse DNA in some supermarket beef burgers.
We've seen the jokes on Twitter but the discovery of horse and pig DNA in beefburgers poses a serious question; where did it come from?