The parents of a toddler who was injured after sticking his hand into a wolf enclosure at the ZooAmerica North American Wildlife Park in Pennsylvania have been charged with child endangerment, authorities said.

The Derry Township Police Department said it is investigating the incident that occurred on Saturday, April 4, at about 11:35 a.m. local time at ZooAmerica in Hershey, Pennsylvania. During the incident, police said an unsupervised 17-month-old child had "squeezed through a small opening in a wooden barrier perimeter fence" and accessed a restricted area near the wolf exhibit.

According to police, the child then reached the primary metal fence enclosure and was injured after putting his hand through the metal fencing.

ZooAmerica previously reported the toddler's age as 18 months old.

"From the injuries sustained, it appears as though one of the wolves in the enclosure instinctively and naturally grabbed onto the child’s hand with its mouth," police said in a statement. "Several bystanders intervened and helped pull the child away."