The News & Observer of Raleigh reported that customers and employees at the restaurant in Knightdale were evacuated Sunday morning and treated for symptoms like burning noses and eyes.
The hazardous materials team from the Raleigh Fire Department responded to the call.
A McDonald's employee said Monday the problem was caused when someone put pepper spray on a hand dryer in the men's restroom. After turning the dryer on, the pepper spray spread throughout the restaurant.