NATIONWIDE -- Chipotle Mexican Grill Inc. has agreed to pay a $25 million fine in relation to nationwide foodborne illness outbreaks between 2015 and 2018, the largest criminal fine ever in a food safety case, the U.S. Justice Department said Tuesday.

• DOJ says Chipotle agrees to pay record federal food safety fine
• Food illnesses from 2015-2018 linked to Chipotles in 4 states
• Chipotle has agreed to improve staffing, training, compliance

In total, more than 1,100 people were sickened in the outbreaks.

Paperwork filed Tuesday in Los Angeles federal court charges Chipotle with adulterating food in violation of the Federal Food, Drug, and Cosmetic Act. But the Newport Beach, California-based company agreed to a three-year deferred prosecution agreement that will allowed it to avoid conviction if it complies with an improved food safety program.

The terms of the agreement include the $25 million fine.

The charges stem from investigations into a handful of foodborne illness outbreaks between 2015 and 2018 that were linked to Chipotle restaurants in metro L.A., Boston, Virginia, and Ohio. They said store employees failed to follow company food safety protocols, resulting in hundreds of employees and customers becoming sick with norovirus or Clostridium perfringens, a bacterium.

Investigators found that in one incident in which 141 people in the Boston area got sick with norovirus in 2015, a sick employee was ordered to continue working even after vomiting in the restaurant. Two days later, investigators said, the same employee helped with a catering order for an area college basketball team, whose members later were among the people who got sick.

In July 2018, almost 650 people who had eaten at a Chipotle in Powell, Ohio, got sick from Clostridium perfringens, which grows when food isn't stored at proper temperatures. The local health department later determined the store had critical food safety violations.

These incidents and others were described in the deferred prosecution agreement, and Chipotle agreed they were true, the DOJ said. Chipotle agreed in the DPA to improve its food safety compliance, audits, restaurant staffing, and employee training.

"The FDA will hold food companies accountable when they endanger the public’s health by purveying adulterated food that causes outbreaks of illness,” said Food and Drug Administration Commissioner Dr. Stephen M. Hahn. "We will continue to investigate and bring to justice any company whose food products present a health hazard to consumers."