Occupational Safety and Health Administration has opened an investigation after two workers construction power lines near Union Star were injured earlier this week.

OSHA said Wednesday it has opened an investigation into a report that two employees of Capital Electric Line Builders Inc. of Riverside were injured while constructing a power line off County Road 206 near Union Star, Missouri, on June 20.

Initial reports indicate the employees were pulling down on a de-energized overhead line under tension when the device holding the line failed and they were struck by the line when it rebounded.

A 40-year-old worker was treated and released from a local hospital and a 36-year-old worker suffered a broken jaw and remains hospitalized.

“These incidents are preventable and OSHA will be conducting a thorough investigation to see if any violations of safety procedures contributed to the injuries suffered by these two workers,” said Todd Sieleman, OSHA’s Acting Area Director in Kansas City.