COLUMBUS, Miss. (WJTV) — A criminal investigation is being launched into the allegations that a fast food worker put menstrual blood on a customer’s hamburger during a drive-thru order, according to WCBI.

The Mississippi State Department of Health went to Jack’s in Columbus, Miss. to investigate the food contamination allegation.

The health department said an inspector was sent to do a routine check after the allegations surfaced. The restaurant passed the inspection, so the allegation was reported to a local law enforcement agency for a criminal investigation.

The Columbus Police Department said they are conducting the investigation.

The allegation received a lot of attention after a person posted on Facebook that a Jack’s employee put blood on a customer’s hamburger.

The restaurant released this statement about the allegations:

Food safety is our top priority at all Jack’s Restaurants. As part of our rigorous food safety program, Jack’s maintains strict food handling policies and procedures that all team members must follow. Jack’s was recently made aware of an audio tape recording posted on social media, which allegedly claims that an employee at a restaurant in Columbus, MS potentially violated our stringent safety standards. The employee allegedly involved in this incident was terminated several days ago for unrelated reasons and no longer works for us. At the time of her dismissal Jack’s was not aware of these allegations. At Jack’s, we take these allegations very seriously and are working to determine the validity of these claims. Additionally, we are committed to taking further action if appropriate.