Three people have died after a sailor shot two civilians and then turned the gun on himself at Pearl Harbor in the United States.
A third victim was taken to hospital and is in a stable condition after Wednesday's shooting, with authorities now trying to determine a motive.
It is believed the shooting took place within the naval shipyard area of a US military base.
"We have no indication yet whether they were targeted or if it was a random shooting," said Rear Admiral Chadwick.
The base went into lockdown at about 2.30pm local time when the first reports were received.
It reopened a few hours later.
Witnesses were still being interviewed hours after the shooting.
It comes just days before thousands were scheduled to gather in the area to mark 78 years since a Japanese bombing on the port, which killed more than 2,300 Americans.
About a dozen survivors of the 1941 bombing are expected to attend, along with dignitaries and service members.
Naval authorities are now evaluating whether security will need to be tightened for the annual ceremony.
The shipyard is across the harbour from the wreckage of USS Arizona, which sank in the Japanese attack.
The base is the home port for 10 destroyers and 15 submarines. It also hosts Air Force units.
Hawaii had the lowest gun death rate among the US states in 2017, according to the Giffords Law Centre to Prevent Gun Violence.
The islands have strict firearms laws, including a ban on assault weapons and large capacity ammunition magazines.