A 43-year-old man has died after suffering burns from a flash fire inside a hyperbaric chamber in Lake Havasu City, Arizona, authorities have said.

Police and fire department units were called to a medical emergency for a burn victim on Wednesday, Lake Havasu Fire Department said in a statement.

The first crews to arrive saw smoke throughout the building and while the chamber remained intact, it appeared a flash fire had occurred, the fire department said — referring to a fire that spreads rapidly through a diffuse fuel such as a gas or flammable vapor.

The man was pronounced dead at the scene and has been named by authorities as Walter Foxcroft, who appeared to be the owner of the clinic.

— The Washington Post