When a utility worker in Key Largo, Florida, noticed that a section of a paved street was not settling properly, he decided to remove a manhole cover and descend into the earth.
Moments later on Monday morning, the 15-foot-deep hole went silent. Sensing the man was trapped, a fellow utility worker climbed into the drainage hole to rescue him. When he, too, stopped responding, a third worker entered the same hole.
All three men died, overcome by poisonous fumes underground, the Monroe County Sheriff’s Office said in a statement. A Key Largo firefighter who made a desperate attempt to save the men also became unconscious within seconds. The firefighter, Leonardo Moreno, an eight-year veteran of the department, was flown to a hospital and was in critical condition Tuesday.
The hole, just wide enough to fit a body, was filled with hydrogen sulfide and methane gas created from years of rotted vegetation, the Miami Herald reported. None of the four men wore masks or carried the air packs that could have likely saved their lives. Moreno descended into the hole without his air tank because he could not fit through the hole with it, according to Monroe County Sheriff Rick Ramsay.