WEST POINT, Miss. (AP) — A Mississippi tire factory says it has fired 29 employees for using fake worker certifications to get jobs.

The unit Yokohama Rubber Co. Ltd. said the workers didn’t meet requirements to get a job at the West Point plant. The Japanese company says it’s investigating and has created safeguards to prevent it from happening again.

The workers obtained fraudulent certificates from a job training program that companies use to determine the aptitude of potential hires.

It’s unclear how the workers got the certificates, or if any other employers were tricked.

Plant President Osamu Zushi says Yokohama won’t let the situation detract from the good work of other employees.

Yokohama has made commercial truck tires in West Point since 2015. The company currently has 665 employees there.