An Illinois boy was killed after crashing a four-wheeled all-terrain vehicle in the Silver Lake Sand Dunes Sunday.

A second 13 year old, a member of the same group, was injured and initially transported to Mercy Health in Muskegon for treatment. He was later transferred to Helen DeVos Children’s Hospital in Grand Rapids to be treated for a broken clavicle and was doing well, Oceana County Sheriff Craig Mast said.

According to Oceana County Sheriff’s Office’s Lt. Shane Hasty, the boys and a third person were traveling north in the dunes on the ATVs when they crested a hill and the machines tumbled end-over-end, landing on top of them. Good samaritans stopped to assist and removed the ATVs from the boys. The individual killed was a Josue Alvarez of Lansing, Ill. Hasty said Alvarez did not have an off-road vehicle safety certification. The second boy, Julian Campos, is also of Lansing, Ill.

No further information was available. The incident remains under investigation.