Sioux Falls Police and the Secret Service are investigating a rash of counterfeit cash.
Fake $10 and $20 bills showed up at ten businesses over the weekend.
The counterfeiters targeted everything from gas stations and casinos to fast food restaurants and drug stores.
Police say at least one of the businesses refused to accept the counterfeit cash.
In other cases, they're studying surveillance video.
Suspect descriptions vary, so at this point, police say it's too early to say if all the cases are linked.