SPOKANE, Wash. -

A Spokane mail carrier is on unpaid leave tonight, under investigation for stealing mail from the customers on her route. The specific charges are “delay or destruction of mail,” and “theft of mail matter by an officer or employee.”

According to co-workers, the woman was caught after she took her private vehicle to a garage for repairs and mechanics found mail addressed to other individuals.

The mechanics thought they were only turning in a mail thief, but investigators quickly learned the suspect was a postal worker herself.

The United States Postal Service says theft by carriers is very rare. In 2013, only 339 were fired for the crime out of a half-million employees. Much more common is non-employee thieves who steal mail from boxes after it's been delivered.

“If you see anyone out there tampering with a mail box, who is not a postal carrier and you know should not be at that mailbox, you need to immediately report it to crime check,” said Robbin Darst with USPS.

The USPS says all potential victims have been notified of the carrier's actions.

If convicted she faces up to five years in federal prison and $250 million in fines.