Things just got messier for Chipotle.

According to Reuters a criminal investigation linked to an August norovirus outbreak launched today. Weird that it starts with a noro outbreak.

Chipotle Mexican Grill Inc said it was served with a grand jury subpoena in relation to a criminal investigation into a norovirus contamination at one of its restaurants in California in August.

The company said the subpoena required the company to produce a broad range of documents related to the norovirus incident at its restaurant in Simi Valley, California which affected nearly 100 people.

The criminal investigation is being conducted by the U.S. Attorney’s Office for the Central District of California and the U.S. Food and Drug Administration’s Office of Criminal Investigations, the company said on Wednesday.