A sightseeing plane crashed in southeast Alaska Thursday killing all nine people onboard, US police said.

Emergency crews were able to reach the aircraft that crashed against a granite rock face and confirm the deceased, but weather in the fjords prevented recovery efforts, Megan Peters from Alaska's Department of Public Safety said.

"Due to inclement weather, the body recovery effort will not be attempted until tomorrow," she said in a statement.

The plane, a single-engine DHC-3 Otter, went down near down near Ketchikan, the Federal Aviation Administration said.

The aircraft was reported to be part of Holland America Line, a cruise line operating in the area.

"We are incredibly distressed by this situation, and our thoughts and prayers are with those onboard the plane and their families," the cruise line said in a statement according to the Alaska Dispatch News.

Holland America Line was not available to comment to AFP on the reports.

The National Transportation Safety Board said on Twitter it was sending a "go-team" to the crash site to investigate.