Three employees with the Bernalillo County Sheriff’s Office and one worker with the county’s fire department were killed in the crash near Las Vegas, New Mexico, the sheriff’s office said on social media.
There were no known survivors, officials added, noting the information is preliminary.
“These personnel were headed back to Albuquerque after assisting fire crews with the East Mesa Fire,” the sheriff’s office said.
The National Transportation Safety Board told CNN it is investigating the crash. New Mexico State Police said the Federal Aviation Administration is also investigating.