ANCHORAGE, Alaska (AP) — Pilots reported low clouds the morning a sightseeing plane crashed near Ketchikan, killing all six people on board, according to a federal report released Wednesday.

The National Transportation Safety Board released the preliminary report into the Aug. 5 crash of a plane that was carrying five tourists off a cruise ship and the pilot. The report did not include details like a probable cause, which are typically released much later.

The plane hit heavily wooded, mountainous terrain as the plane was returning to the Ketchikan harbor from a trip to Misty Fjords National Monument, the report said.

The NTSB preliminary report said the accident site was 18 miles northwest of Ketchikan, but Clint Johnson, head of the NTSB’s Alaska division, told The Associated Press on Wednesday that the location was actually northeast of Ketchikan. After the crash, Johnson initially said the crash was 12 miles northeast of the city, not 18. He said Wednesday that the 12-mile figure was preliminary.

The plane initially hit a tree about 435 feet from the main wreckage location. The plane’s major components were found near the main wreckage, according to the report.

The report said other pilots who were conducting passenger flights that morning said there were low clouds in the valley where the accident occurred.

Pilots who assisted in the search for the plane said the weather was overcast, and the mountain tops were obscured.

The clouds were as low as 600 feet to 800 feet in some places, including the valley where the accident occurred, the report said.