Transcript for Chipotle Facing Criminal Investigation Over Norovirus Outbreak

Now to more trouble for chipotle. The fast food chain now facing a criminal investigation over the norovirus outbreak at a California outlet that left hundreds sick. ABC's Clayton Sandell has the latest. Reporter: This morning fast food chain chipotle is involved in a criminal investigation. The company revealing in a regulatory S.E.C. Filing that it was served with a federal grand jury subpoena last month asked to produce a broad range of documents in connection to a norovirus outbreak at this franchise in California's simi Valley last August that sickened 234 people. The burrito giant says it does not know whether it will bring fines or penalties. The U.S. Attorney's office working with criminal investigators from the fda, both offices declining to comment. Chipotle telling ABC news, it will cooperate fully with this investigation. The department of justice is taking this so seriously and it is definitely on their radar. Reporter: After the summer outbreak, the restaurant was closed to are a deep clean but the company that prides itself on serving food with integrity is struggling to regain consumer trust taking out full page ad as poll justing to consumers and announcing coming changes to the way it prepares and tests its food. After making headlines for two E. Coli outbreaks sickening people in 12 states and a norovirus outbreak in Boston which sickened 140 college students who ate at this store. And now it seems as though wall Street is getting a bit queasy. Chipotle's stock price is down 40% since their troubles began.

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