Michigan Attorney General Dana Nessel has charged four people in connection with the death of a 5-year-old boy who was killed in a hyperbaric chamber explosion in Troy, Michigan.The four were arrested Monday morning and arraigned Tuesday afternoon.

Police in Michigan have arrested four people after a 5-year-old boy receiving treatment at The Oxford Center died when the hyperbaric chamber he was in exploded.

The facility where a hyperbaric chamber fire killed a 5-year-old child “held safety among their lowest considerations,” the Michigan attorney general said.