WILLITS, Calif. -

When a Burger King customer checked her cheeseburger for onions, she claims she found a razor blade on the patty instead.

The California woman says she took a bite of the sandwich before noticing the razor blades. However, she didn't bite into the blade and wasn't hurt.

The woman contacted local authorities, who discovered Burger King workers use the razor blades for cleaning. Police discovered three more razor blades near food at the fast food restaurant. Officers determined the blade was not intentionally put on the burger.

In a statement, Burger King said the company believes food safety is a "top priority" and explained it is up to franchise managers to "emphasize the proper food safety procedures to all crew members."

A Burger King spokesperson told USA Today the company would make sure there are no razor blades in restaurants moving forward.