Police are investigating a May 4 incident at Yosko Park in which a planned fight between groups of juveniles involved a replica gun.

Officers were tipped off and monitoring the area via city cameras when a physical altercation set off around 6:45 p.m. One young man was observed removing an object from a backpack, believed to be a firearm, and placing it in his waistband. When officers arrived the item was returned to the backpack, which was in the possession of an adult female. While she was detained, a large crowd gathered along East Sixth Street, shouting and encroaching on the investigation scene.

The crowd ultimately complied with commands to stay back.

A replica airsoft Glock Gen4 17 pistol was found in the backpack.

Two adults and two juveniles are facing charges and additional arrests may be forthcoming in the investigation in consultation with the Northampton County District Attorney’s office.