The authorities at a military base in Hawaii were responding on Wednesday to reports of a shooting at the Pearl Harbor Naval Shipyard.
Reports of the shooting at the Joint Base Pearl Harbor-Hickam came in around 2:30 p.m. local time.
It was not immediately clear if anyone had been injured. A woman who answered the phone at the base said it had been placed on lockdown.
The base, on Oahu’s South Shore, hosts both the Air Force and Navy.
The episode happened three days before the 78th anniversary of the sneak attack by Japan on the United States Naval Base at Pearl Harbor, which President Franklin D. Roosevelt termed as a “date which will live in infamy.”
The raid killed more than 2,300 Americans and devastated the Navy’s Pacific fleet. All but one of its Pacific battleships were in port that day, including the U.S.S. Arizona, which sank.
The wreckage is now a memorial park. Congress declared war on Japan the next day. On Dec. 11, 1941, the United States went to war with Germany and Italy, Japan’s allies.