At least one person was killed and three others injured when a United States sailor opened fire at the Pearl Harbor Naval Shipyard on Wednesday, striking three Department of Defense civilian workers before shooting himself, the authorities said.
It was not immediately clear who had died. The shooting was reported around 2:30 p.m. at a dry dock on Joint Base Pearl Harbor-Hickam.
The base was quickly placed on lockdown, but around 4 p.m., people were again allowed to enter and leave the base.
The motive for the shooting, which remains under investigation, was not immediately clear. The base said that the names of the victims would not be released until next of kin were notified.
The base, on the southern shore of Oahu, hosts both the Air Force and Navy.
The episode happened three days before the 78th anniversary of the Japanese sneak attack on the United States Naval Base at Pearl Harbor, which President Franklin D. Roosevelt called 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 Arizona, which sank.
The wreckage is now a memorial park. Congress declared war on Japan the day after the attack. On Dec. 11, 1941, the United States went to war with Germany and Italy, Japan’s allies.
The shipyard where the shooting was reported to have taken place is about a mile from the U.S.S. Arizona Memorial.
Live videos showed ambulances and police vehicles at the base.
Outside the Pearl Harbor National Monument, tourists were stunned by an announcement that there was an active shooter on the base.
Ruth Kenneway, 52, said she heard an announcement directing people to “shelter in place.”
Ms. Kenneway, who was visiting the area from Fremont, N.H., said her friend was a civilian contractor at the shipyard.
“It’s frustrating because Pearl Harbor day is coming up and I worry about it,” Ms. Kenneway said. “There were 40 to 50 Marines, young fellows, setting up for the ceremonies for Pearl Harbor day.”
Brenda Sudol, 61, said that “everyone was looking at each other because they didn’t know what to do.”
“We knew we were in lockdown,” she said. “I was going to go behind the bushes or on the ground or in the building,” Ms. Sudol said.
Michelle Broder Van Dyke, Jaclyn Peiser and Thomas Gibbons-Neff contributed reporting.