PEORIA, Ill. -- Employees at Avanti's on Main Street say a complaint from an unhappy customer led to the police being called on Wednesday evening.
According to a report, the suspect was angry that there was a hair in his food and demanded a refund.
The Avanti's employee refused to refund him because he had eaten most of his food.
After a manager asked him if he still had the hair, the suspect left the building and returned to the store a few minutes later.
A customer then reported that she noticed a gun tucked in his waistband, which prompted employees to call police.
The suspect told the employee he would "be waiting for him to get off" and left the restaurant.
Authorities are reviewing video footage from the incident to identify the suspect.