A criminal act almost certainly led to horsemeat finding its way into beefburgers sold by major supermarkets, the government has warned.

Prosecutions are likely as a result of the scandal, farm minister David Heath suggested to MPs on Thursday (17 January).

“We are talking about, almost certainly, real criminality,” said Mr Heath, responding to an urgent question from shadow DEFRA secretary Mary Creagh in the House of Commons.

Beef products that tested positive for horse DNA have been removed from sale in Tesco, Lidl, Aldi, Iceland and Irish retailer Dunnes Stores.

In one case, horse accounted for 29% of the meat content in Tesco beefburgers.

Ms Creagh asked why the contamination had been uncovered by the Food Safety Authority of Ireland, rather than the UK Food Standards Agency.

“Testing, tracking and tracing ingredients is expensive, but not testing will cost retailers, processors, British farmers and consumers much more,” she said.

Earlier, the parent company of two meat processors involved in the scandal said it was “shocked” by the contamination and was taking the matter extremely seriously.

The ABP Food Group said it would take an “industry lead” in DNA testing of products should independent testing for equine and porcine DNA be proved.

ABP operates the Dalepak Hambleton plant in Yorkshire and the Silvercrest Foods plant in Ireland, both of which supply major retailers with processed meat products.

“We take this matter extremely seriously and apologise for the understandable concern this issue has caused,” said an ABP statement sent to Farmers Weekly.

“ABP Food Group companies have never knowingly bought, handled or supplied equine meat products,” the statement said.

“We acknowledge the understandable concern created as a result of the Food Safety Authority of Ireland’s DNA frozen beefburger test results.”

ABP said the issue only affected frozen beefburgers supplied by Silvercrest Foods and Dalepak Hambleton. There was no food safety issue, it insisted.

“Our group companies only buy meat from licensed and approved EU suppliers. These results relate only to where beef products have been sourced by those suppliers from the Continent.

“Only a small percentage of meat is currently procured from outside of the UK and Ireland. Fresh meat products are unaffected.

“We are shocked by the result of these tests, and are currently at a loss to explain why one test showed 29% equine DNA.”

Investigations are centring on beef products supplied to Dalepak and Silvercrest Foods by two European companies, believed to be based in the Netherlands and Spain.

“We are conducting our own DNA tests on a wide number of samples and expect the results in the coming days,” said the ABP statement.

It added: “While extensive and thorough safety checks are conducted on all meat products, the industry does not routinely DNA test meat products.”

As a result of the incident, ABP said it was implementing a new testing regime for meat products that would include DNA analysis.”

“Should our own testing prove positive, we are also considering our options in respect of the two [European] suppliers concerned.

“It is vital that the integrity of the supply chain is assured and we are committed to restoring consumer confidence,” the statement said.