The US Army Garrison-Kwajalein Atoll,which supports a space and missile defence test site,evacuated about two-thirds of the 120 American and Marshallese personnel who live and work there,the army said.
Video posted on social media showed smashing windows and doors of an army building,and sweeping people from their feet on Saturday.
A man shouts “keep the doors closed” before they are ripped from their hinges by the force of the waves.
The army reported only minor injuries and was working to restore basic functionality to the island post and facilitate the supply of clean water and fuel.
“Clearing the runway on Roi-Namur and assessing its safety is our top priority now that we have evacuated personnel not required for the initial response efforts,” said Colonel Drew Morgan,the garrison commander.
“Once the runway is open,we can move people and equipment back and forth to start the recovery process.”
The army said the recovery operation could take months. It said housing,religious,dining and entertainment facilities were moderately to severely damaged,while the island’s automotive complex was completely submerged.
Roi-Namur,the second-largest island of Marshall Islands’ Kwajalein Atoll,sits about 4000 kilometres north-east of Australia.
It is home to American radar systems that can track intercontinental ballistic missiles and spacecraft as they re-enter the Earth’s atmosphere.
The landmass – originally two separate islands,Roi and Namur – was created when the US Navy filled the space between them late in World War II after the Americans took the Kwajalein Atoll from Japan,who had controlled it since the end of World War I.
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