Juneau, Alaska, Aug 21: Eight people were killed after a civilian-contracted charter aircraft crashed near a remote radar installation in western Alaska, authorities said.

The aircraft went down on Thursday while approaching the Cape Newenham Long Range Radar Site Airport, located around 450 miles (725 kilometres) west of Anchorage.

According to the National Transportation Safety Board (NTSB), the aircraft was carrying two pilots and six passengers. It had departed from Anchorage and was believed to have crashed during its approach to Cape Newenham.

The remote facility is managed by the Pacific Air Forces Regional Support Center and forms part of a network of radar installations used to monitor aircraft operating in and around Alaska's airspace and along its borders. The military described the aircraft as a civilian-contracted plane, but did not immediately disclose the specific work being carried out by those on board.

US Air Force Lt Gen Robert Davis, commander of Alaskan Command, the Alaskan North American Aerospace Defense Command Region and the Eleventh Air Force, described the incident as a devastating loss.

Davis said the people aboard the aircraft were professionals involved in an important mission in a challenging environment. He also expressed condolences to their families, friends and colleagues and praised the search and recovery teams for their response.

The crash occurred in a remote part of western Alaska, where access and recovery operations can be challenging. Authorities have not yet released further details about what caused the aircraft to go down.

The NTSB is expected to investigate the circumstances surrounding the crash, including the aircraft's final approach and the factors that may have contributed to the accident.

The identities of those killed had not been publicly released in the initial reports.