The department said staff saw the boys passing the basketball courts where day campers were playing at the school around 3:30 this afternoon.

Staff called 911 and took the children inside, placing the school on lockdown, according to a news release from the department. The four boys are now in custody of the Gainesville Police Department.

After the incident, parks officials released a statement that read:

"Please know that our primary concern is the well-being of our participants. Our staff has been thoroughly trained by experts in various fields to protect participants of all Gainesville Parks and Recreation events and programs in emergency situations and took appropriate action to ensure their safety," said J. Melvin Cooper, Gainesville Parks and Recreation Director.

Agency management and camp directors were on site to speak with parents when they picked up their children from the camp.

In addition, letters to all parents of camp participants are being prepared detailing the incident, the department said.