Franklin Township Police Department said it was investigating the incident, which Mayor John Bruno and Police Chief Brian Zimmer described as "revolting" in a joint statement.
"The Franklin Township Committee and its Police Department are appalled and saddened by the revolting actions of certain individuals after Monday's locally organized Peaceful March," they wrote. "This is not who we are as a community."
"We support the goal of this march which is to spread awareness and to ensure a better future for all of us. Without an understanding and mutual respect for all individuals, we can never aspire to create a united community based upon the idea of human respect and dignity for all."
The protest march, like countless others across the country, took place on the day before George Floyd was laid to rest beside his mother.
He died on May 25, after Minneapolis police officer Derek Chauvin knelt on his neck for almost nine minutes, after arresting him over an alleged fake $20.
Chauvin has since been charged with second-degree murder and second-degree manslaughter, while the three other officers that were involved in the arrest — Thomas Lane, J.A. Keung and Tou Thao — have also been charged with aiding and abetting the homicide.