Bed bugs have invaded a Milwaukee County services building again.

Officials said a dog detected a small number of the insects inside an isolated area at the Marcia Coggs Center in downtown Milwaukee.

The building was dealing with the same problem just over a year ago.

Monday night, CBS 58 saw crews with Batzner Pest Control unloading equipment to go inside the building and begin the extermination process.

County spokesperson Melissa Baldauff said bed bug reports are common in public spaces, as often times, they come in off of visitors.

"The county has an active pest control contract so that we can both take proactive measures to prevent these occurrences and respond quickly when remediation is needed," she said in a statement.

Baldauff said the Coggs Building remains safely open to employees and the public. Click here for ways to protect yourself from bed bugs in public places.