Why did the Californian food processor recall their products?

A California food processer is recalling 5,400 cases of bagged salad because of possible E.coli contamination. The products were distributed in 15 states.
    Ready Pac Food is just voluntarily recalling a dozen different bagged salads. They were sold in supermarkets under the Ready Pac, Trader Joe’s, Safeway and Dinning In Classic labels. The packages were stamped with the "use by date of November 8th". The suspect products were sold primarily in western states including California, Texas and Colorado. Inspectors are trying to pinpoint the source of the contamination. There hadn’t been any reported illnesses that are attributed to the products in question.
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