The North County News reported Monday that a Red Bud bank believes it may have received two counterfeit $100 bills from two separate businesses.

The bills were discovered Monday morning in the bank’s weekend deposits from fast food places. As deposits were being run through a teller cash machine, the bills were pulled out and flagged as possible counterfeits, prompting tellers to take a closer look.

It was noted that the bills are both series 2006, with serial numbers KB887691–B — the last two numbers being different.

When compared to another $100 bill from 2006, these suspect bills feel thicker and the back of the bill is blurry. In particular, the “In God We Trust” is blurry. The ink color is also off, the newspaper reported. There is also a strip inside the bills that would normally note the bill denomination, but the strips in both were unreadable. Unfortunately, counterfeit detection pens are not working on these bills.

Both of the possible counterfeit bills have been sent to the U.S. Secret Service for testing. It may take up to a few weeks for results to come back.