Burger King has announced that they were one of the companies affected by the recent discovery of horse DNA inside hamburger patties.

Three processing plants–including Silvercrest Foods, which supplied UK and Ireland Burger King stores with their hamburger–have been under investigation for their use of horse meat in their products after the Food Safety Authority of Ireland conducted tests, which also found pig DNA. The companies also supply grocery stores in the UK and Ireland with the meat. And while BK says the meat tested in their restaurants was negative for horse DNA, they do admit they have used meat sourced from Silvercrest and have changed their supplier.

“Our independent DNA test results on product taken from restaurants were negative for any equine DNA,” the company said in a statement. “However, four samples recently taken from the Silvercrest plant have shown the presence of very small trace levels of equine DNA. Within the last 36 hours, we have established that Silvercrest used a small percentage of beef imported from a non-approved supplier in Poland. They promised to deliver 100% British and Irish beef patties and have not done so. This is a clear violation of our specifications, and we have terminated our relationship with them.”

While the Food Safety Authority of Ireland says there is not health risk to be had from eating what some are calling “tainted” meat, the news has consumers across the pond worried and Silvercrest is losing clients left and right, including Aldi, Tesco, and Asda.