Chipotle Mexican Grill Inc., which is trying to recover from a series of food-borne illness outbreaks, temporarily shut a Massachusetts restaurant after four employees fell sick.
The restaurant in the town of Billerica, outside Boston, was closed for a full cleaning, company spokesman Chris Arnold said by email.
Chipotle's shares fell 3.8 percent to $504.50 in extended trading.
"No customer illnesses are connected to this restaurant. Any employee who reported feeling ill will be held out of the restaurant until they fully recover," Arnold added.
Chipotle is trying to repair its reputation after suffering several food-related illnesses, including two E.Coli outbreaks that sickened about 50 people in 14 states and two separate norovirus outbreaks in Massachusetts and California.
The Massachusetts health department confirmed that the restaurant was closed voluntarily and that no customers were known to be sick, according to a Bloomberg report.
The department was not immediately available for comment.