Horse meat was discovered in products that are supposed to be 100% beef, sold in Sweden, the United Kingdom and France.
On Sunday, a major company under scrutiny called one of its suppliers a "villain" responsible for the fraud. The supplier, in turn, insisted it was "fooled" by a subsupplier.
While authorities say there is no immediate cause for health concerns, the discovery was a new shock to an industry already reeling from a bombshell last month when Irish investigators found horse and pig DNA in numerous hamburger products.
The blame chain
Europe deals with horse meat scandal
Swedish food producer Findus has been a focus of the uproar since it announced Thursday that it had withdrawn its lasagna from stores as a precaution. The products were pulled Monday after French supplier Comigel raised concerns about the type of meat that was used, Findus Sweden said.
Findus said a letter from Comigel dated February 2 informed Findus that the contamination may date back to August 2012.
Horsemeat found in hamburgers in Britain and Ireland
Findus is only one of several companies that receive products from Comigel. Others include Axfood, Coop and ICA, which have recalled some meat products in Sweden, and Aldi, which has pulled some products from shelves in Britain.
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