All six people aboard a helicopter were killed when it went down in a rural area of Logan County, West Virginia, Wednesday evening.

The Bell UH-1B crashed at about 5 p.m. near Route 17 highway, according to the Federal Aviation Administration.

Ray Bryant, chief of operations for Logan Emergency Ambulance Authority, confirmed in a news briefing that all six people aboard died. The helicopter was based out of Logan County Airport, Bryant said, and was used for recreational tours.

The names of the victims and the circumstances of the crash were unclear. 

Bryant said the helicopter was from the “Vietnam era.” According to the Heritage Flight Museum, the Bell UH-1 is a military helicopter first manufactured in the 1950s and used extensively during the Vietnam War.

As is standard policy, the FAA and National Transportation Safety Board will investigate. The NTSB reported that it had five investigators headed to the scene.

Meanwhile, West Virginia Gov. Jim Justice tweeted: “Cathy and I are praying for the families of those killed in this tragic helicopter crash.”