An accidental release of pepper spray is believed to be what caused patrons to cough suddenly at a Denny’s restaurant in Santa Monica Sunday afternoon, December 30th, leading to an evacuation of the restaurant, Santa Monica fire officials said.

Santa Monica firefighters were called to the restaurant at 1560 Lincoln Blvd. at about 12:15 p.m., after patrons had begun coughing for an unknown reason and reported a “nauseous smell” and having irritated eyes, Santa Monica Fire Department Capt. Scott Ziegert said.

A Los Angeles County Fire Department hazardous materials unit was also called to assist.

Restaurant patrons and employees were evacuated and examined by paramedics but no one was taken to a hospital, Ziegert said.

Firefighters scanned the building and determined that the problems were probably caused by an accidental release of pepper spray, he said. It was unknown where the spray originated.

No arrests were made in the incident.

After firefighters ventilated the building for the spray, the restaurant reopened that night, hours after the incident began.