HARTFORD, Wis. -- The Hartford Police Department is currently investigating several incidents of counterfeit $100 bills being passed.

It happened at several businesses in Hartford and in neighboring jurisdictions.

In a post on social media, Hartford Police stated: ". It is important to understand how to identify some of these bills, as most are "washed" bills of a lower denomination. Most of these bills will pass the counterfeit pen test as well, because they are actual bills that have been washed to remove the original printing and then reprinted in a larger denomination."

If you are questioning the authenticity of a bill given to you, call Hartford Police.

For more information on identifying fake bills, click here.