Kennewick police are warning about counterfeit money being passed around town.
Fake $5, $10 and $20 bills recently have been found in deposits made by businesses, said Sgt. Ken Lattin.
Detectives are investigating an incident Friday when five counterfeit bills were used at Yoke's Fresh Markets, he said.
It's one of about a half dozen instances so far where the phony money has turned up, he said.
Three fake $20 bills and some $5's were used at Tesoro Food Mark, 528 S. Ely St., on Jan. 8 and 10.
A counterfeit $20 was passed at Twigs Bistro on Sunday, and Banner Bank reported Tuesday getting a fake $10 bill in a deposit from one of the McDonald's restaurants, Lattin said.
Westgate Elementary School staff also discovered Monday that they had been given a counterfeit $5 bill sometime in December.
Many businesses don't detect counterfeit money immediately, making it a challenge to track down the suspects, authorities said.
"We don't tell people what bad bills look like, we train people on what good bills look like," Lattin said.
Bills can be counterfeited in numerous ways, he said, so knowing what legitimate bills look like is key.
Checking serial numbers and looking for the security thread embedded in the paper and the watermark are ways to verify the money is real.
Officials urge store clerks to call police immediately if they receive counterfeit money.