MORGANTON, N.C. -- Burke County investigators said that since the first of the month, they've seen about every kind of counterfeit bill.

They said they know of at least 20 businesses in the Morganton area have taken the money, but public safety officers said they are making progress in the case.

Investigators said they seized computers, printers and paper from a home on Friday. They want to know if the equipment was used to make the counterfeit money that has shown up at restaurants across the area, including a bogus $20 and a $5 passed at the Tokyo Diner this week.

"I think they came in a time when we were busy. I think maybe through the drive-thru and handed it over,” said the restaurant’s manager, Si Lor.

It wasn't until the next day the restaurant leaned the bills were bogus.

Public Safety officers said the person passing the counterfeit cash is hitting fast food restaurants at their busiest times. A quick glance and the money looks real, but it isn't.

"Some people knew instantly it was fake. Some people don't even know as of yet it is fake. It was pretty good quality, but the Secret Service said it wasn't the best of quality," said Detective Calvin Daniels of Morganton Public Safety.

It was a worker here at a Mcdonald’s in Morganton who spotted the counterfeit money and got a tag number that’s helping investigators.

Public safety officers said they do have a person of interest and others may be involved, but they have not charged anyone yet.

Investigators said thousands of dollars of counterfeit cash was printed, and some of it may still be out there.

Detectives are working with the Secret Service. They said their next move is to test the paper seized from that home to see if it matches the paper of the counterfeits.