MONTREAL -- Quebec’s alcohol retailer, the SAQ, has suspended one of its cashiers who allegedly punched a customer multiple times in the head Thursday.

The fight broke out after the customer refused to be served by a cashier who allegedly was not wearing a mask.

The customer, Mario Gosselin, says he still feels shaken by the event.

"I thought I was being killed,” he told CTV. “I thought he was killing me."

Gosselin had been waiting in line at the SAQ in Montreal North when he says he heard the unmasked cashier mocking public health measures.

Gosselin says he heard the cashier brag that his girlfriend is unvaccinated. He asked to be served by someone else.

“I didn't feel comfortable,” he said. “So, I asked to be served by another clerk, who declined to serve me and got aggressive.”

That second clerk  then called a manager on his phone, Gosselin said. The clerk handed the phone to Gosselin and the manager said his employees were not obligated to serve him.

Frustrated, Gosselin says he slammed the employee’s phone down on the counter and turned to leave.

"I was angry and was heading for the door when he came toward me and punched me three times on the head."

Gosselin alleged he was knocked back into a stack of wine bottles, shattering them. While he was lying on the floor, he says an employee approached him and put a knee on the side of his head.

"I thought 'this person is losing it and they're going to kill me',” he said. “When I was on the ground with my head compressed ... my neck compressed ... I really thought I was dying."

He says he suffered minor injuries, and filed a police report the next day. He wants to press charges.

Police confirmed to CTV News that an altercation took place, and an investigation has begun.

Meanwhile, the SAQ has started its own investigation, and the employee has been suspended indefinitely.

"We need to all take a step back and reflect,” said psychologist Linda Pagani, who says two years of lockdowns, restrictions and COVID-19 anxieties have everyone feeling on-edge.

“(We all need to) try to train ourselves to be a bit more positive about other human beings," she said.