BREWSTER COUNTY, Texas (News Nation/KXAN) — Three Texas Parks and Wildlife Department employees were killed in a helicopter crash in West Texas Saturday.

The victims have been identified as wildlife biologist Dewey Stockbridge, fish and wildfire technician Brandon White and state wildlife veterinarian Dr. Bob Dittmar.

The group was conducting aerial surveys for desert bighorn sheep in Brewster County when the aircraft crashed, the Texas Parks and Wildlife Department said.

The pilot of the helicopter, a private contractor, survived the crash.

Carter Smith, TPWD executive director, described the three men as “consummate professionals, deeply liked and highly regarded.”

“No words can begin to express the depth of sadness we feel for the loss of our colleagues in this tragic accident,” Smith said. “Wildlife conservation in Texas lost three of its finest as they so honorably and dutifully carried out their calling to help survey, monitor and protect the bighorns of their beloved west Texas mountains. We will miss Dewey, Brandon, and Dr. Bob deeply and dearly.”

The Texas Department of Public Safety, the Federal Aviation Administration and the Texas Game Wardens are investigating the incident.