TEMPE, AZ -- Tempe police say gunfire damage was found at an Arizona Democratic campaign office on Monday.

Officials say it happened near Southern Avenue and Priest Drive.

Police say the incident is "being investigated as a property crime as no one was in the office at the time of the occurrence."

The Mesa Forensic Unit is assisting Tempe police in the investigation.

The investigation remains ongoing.

It is unknown what led to the incident.

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