SMETHPORT, Pa. — An official says a helicopter carrying workers stringing power lines for a new transmission project crashed in northwestern Pennsylvania, killing two contractors and injuring the pilot.

A spokesman for Akron, Ohio-based FirstEnergy says the contractors were doing work on behalf of the power company but were not their employees. FirstEnergy is building a new, 15-mile project in McKean County.

Doug Colafella says the two contractors worked for Akron-based J.W. Didado Electric. The pilot, whose condition has not been released, was working for High Line Helicopters.

State police say the crash occurred around 5:25 p.m. Sunday near Smethport, about 150 miles (241 kilometers) northeast of Pittsburgh.

No identities have been released.

The Federal Aviation Administration and the National Transportation Safety Board are investigating.