A United States of America navy sailor has shot dead two civilian workers before turning the gun on himself at Pearl Harbour military base, the BBC has reported.
The unnamed sailor also fired at another worker but managed only to injure him before killing himself.
“We have confirmed that two (victims) are deceased," Rear Admiral Robert Chadwick, a regional commander said as quoted by Reuters.
"Obviously our thoughts are with the families of the victims and everyone involved," he added.
Law enforcement authorities placed the Joint Base Pearl Harbor-Hickam under lockdown.
The fatal shooting was reported to the authorities at about 00:30 GMT.
The motive that drove the sailor to shoot with fatal intent has not yet been revealed, the New York Times reported.
Investigations, conducted by base security and the Naval Criminal Investigative Service, into the incident are ongoing.
Hawaii's governor sent out his condolences to the families of the victims of the shooting.
"I join in solidarity with the people of Hawai‘i as we express our heartbreak over this tragedy and concern for those affected by the shooting. Details are still emerging as security forces at Joint Base Pearl Harbor Hickam investigate. #PearlHarbor," the governor's tweet was quoted by BBC.
Senator Mazie Hirono also conveyed her condolences.
"While the investigation into this incident continues, my thoughts and aloha are with the victims of the terrible tragedy at #JBPHH and with their families. I join all of Hawaii in expressing our gratitude to the first responders who rush toward danger every day to keep us safe," he said.