TROY, MI -- An investigation is underway, but officials in Troy have confirmed a 5-year-old Royal Oak boy was killed Friday in an explosion at a medical facility.

A hyperbaric chamber exploded with the child inside, according to the Troy Fire Department. When first responders arrived on the scene, they determined the child, a 5-year-old boy from Royal Oak, was dead. The boy’s mother, who was standing next to the chamber, also sustained injuries to her arm, The Ann Arbor News reports.

A 5-year-old Michigan boy was killed Friday morning when a hyperbaric chamber he was inside of exploded, officials said. Police and firefighters responded to The Oxford Medical Center in Troy around 8 a.