A volunteer firefighter and two contractors were killed Feb. 1 in the collapse of two cell phone towers in Clarksburg, West Virginia.

News sources report that four workers were tethered to a 300-foot-tall tower while making repairs when the structure fell. Kyle Kirkpatrick, 32, of Hulbert, Okla., and Terry Lee Richard Jr., 27, of Bokoshe, Okl were killed; the other workers were hospitalized with serious injuries.

The collapse of the tower put stress on a guy wire, causing a smaller, nearby tower to fall as well, killing firefighter Michael Dale Garrett, 28, who was responding to the scene. Garrett was a member of the Nutter Fork Volunteer Fire Department. A second firefighter was injured in the incident.

Kirkpatrick and Richard were employed by S&S Communications Specialists, an Oklahoma-based company that builds, modifies and performs maintenance on telecommunications towers.

OSHA is investigating the accident