A Massachusetts Buffalo Wild Wings is under investigation after a chemical mixture in the kitchen killed one employee and left at least 10 staff members and customers hospitalized Thursday, authorities said.

According to Boston’s WHDH-TV, the fire department responded to the restaurant in Burlington, Mass., just after 5:30 p.m. A team of firefighters wearing hazmat suits found a male worker suffering from nausea.

Interim Burlington fire chief Michael Patterson said at a news conference Thursday that the man had been exposed to the chemical, which was being used to clean the floor, after someone else mixed it and became ill.

The man, who has not yet been named, was rushed to a hospital, where he later died. Authorities said that at the time he inhaled the fumes he was trying to save others from the chemical.

Boston 25 News reported the chemicals involved as being Super 8, a common floor cleaner whose active ingredient is sodium hypochlorite, and Scale Kleen, an acid-based surface cleaner that spilled as the floor cleaner was being used.

Buffalo Wild Wings has Maine locations in Auburn, Bangor, Topsham and South Portland.

A manager at the South Portland restaurant, who declined to provide his name, said the chemicals involved in the Burlington incident are not used at that restaurant.

Staff members at other locations in Maine declined to comment or referred a reporter to other officials within the company. An email to the company’s media center was not returned Friday night.

The food chain also made headlines earlier this week. On Wednesday, staff at a Buffalo Wild Wings in a strip mall in Naperville, Ill., ordered a mostly African American group of customers to switch tables because another patron did not want to sit next to black people.

The troubling example of public discrimination was captured online and went viral.

A statement released Thursday by a Buffalo Wild Wings spokesperson said, “We are shocked and saddened to learn of this horrific accident at our franchise-owned sports bar and are working closely with our franchisee and the authorities while they conduct an investigation.”

Local authorities continue to investigate the incident. Patterson urged people who were at the restaurant Thursday to seek medical attention.

Press Herald Staff Writer Rachel Ohm contributed to this report.

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