An investigation into why a hospital ship ran into the dock of the USS Arizona Memorial in May says human error caused the incident.

The U.S. Military Sealift Command released the report Wednesday. It says the harbor pilot on board the USNS Mercy had poor control over tugboats guiding the ship out of Pearl Harbor.

The report says this resulted in the ship unexpectedly heading toward the Arizona. It also led the pilot and the ship's captain to lose situational awareness of where the ship was going.

The May 27 incident forced the Navy and National Park Service to close the national landmark for over a week while crews repaired the dock.

The memorial honors the 1,177 sailors and Marines killed on the Arizona in the 1941 Japanese attack.