DUBLIN — The Irish meat company at the center of Europe’s “horseburger” scandal on Tuesday blamed the contamination of its hamburger patties on the purchase last year of 170 tons of meat imported from Poland.

As Ireland struggled to contain the damage to its reputation as Europe’s top beef exporter, the ABP Food Group shed new light on how burgers made partly of horse ended up on British and Irish supermarket shelves. Ireland’s biggest beef company said it purchased the Polish meat last year marked as “beef” from an Irish meat trader, McAdam Food Products, and the product was used by its Silvercrest food processing facility to make frozen beef burgers sold across Britain and Ireland.

The company said in a statement to The Associated Press that “while Silvercrest purchased these beef products in good faith, horse DNA originating in Poland was present in some of these products.”

Confirmation of the scale of ABP’s Polish purchases — at odds with the company’s promise to customers to produce all-Irish patties — came hours after Irish Prime Minister Enda Kenny vowed that Ireland would pinpoint the source of the horsemeat.

Poland says its investigations have produced no evidence of horsemeat shipments.