A small U.S. Army Corps of Engineers-chartered plane crashed Thursday in western Alaska, killing all eight people aboard.

The twin-engine Cessna 441 was traveling from Anchorage to a remote military radar site near Cape Newenham when it went down in rugged terrain and foggy weather.

The aircraft had attempted to land once but missed the approach before losing contact with air traffic officials.

The NTSB and FAA are investigating the crash, examining weather conditions, pilot communications and other possible factors, CBS News has reported.

Two of the victims were Corps of Engineers employees, and military officials expressed condolences to the families and described those aboard as professionals carrying out an important mission.