Chipotle disclosed Thursday that it received a subpoena from U.S. federal prosecutors related to a 2018 food-safety incident at a Powell, Ohio, location. Chipotle briefly closed the restaurant after reports of illnesses surfaced on the website

In August, Chipotle confirmed that a type of bacteria that forms when food is left out at unsafe temperatures caused the outbreak. Nearly 700 people reported gastrointestinal problems, including diarrhea and fever, after eating at the store from July 26–July 30. The Centers for Disease Control and Prevention’s findings credited clostridium perfringens, one of the most common causes of food poisoning in the U.S., for the incidents.

READ MORE: Chipotle rides the digital boom to stellar Q1 results.

Chipotle revealed Thursday’s news in a Securities and Exchange Commission filing, saying the new subpoena requested information related to specific restaurants in Simi Valley, California; Boston; Sterling, Virginia; and Los Angeles that were covered under previous subpoenas, plus the additional Ohio restaurant in Powell.  

Chipotle was served subpoenas related to food-safety incidents on January 28, 2016; July 19, 2017 (Sterling, Virginia); and February 14, 2019 (Los Angeles).

The subpoena came from the U.S. District Court for the central District of California in connection with a criminal investigation conducted by the U.S. attorney’s office in conjunction with the FDA.

“We have fully cooperated and intend to continue to fully cooperate in the investigation,” Chipotle said. “It is not possible at this time to determine whether we will incur, or to reasonably estimate the amount of, any fines or penalties in connection with the investigation pursuant to which the subpoenas were issued.”

New CEO Brian Niccol has taken several measures to curb Chipotle’s food-safety woes, and turn sentiment lingering from the 2015 E. coli outbreaks. In September, it deployed Zenput, a platform used by Domino’s and KFC, to “ensure every location adheres to standards, procedures and initiatives in order to deliver a consistent guest experience.” The mobile platform allows leaders to use the app as a checklist for Chipotle’s food-safety standards.

Following the Ohio incident, the brand said it would retrain all restaurant employees on food safety procedures, with the daily routine augmented.

“Chipotle has a zero-tolerance policy for any violations of our stringent food safety standards and we are committed to doing all we can to ensure it does not happen again. Once we identified this incident, we acted quickly to close the Powell restaurant and implemented our food safety response protocols that include total replacement of all food inventory and complete cleaning and sanitization of the restaurant,” Niccol said in a statement at the time.

Fast Casual, Food Safety, Story, Chipotle