The alert of an incoming ballistic missile was sent wrongly on Saturday morning by an emergency system worker.
Victims of the ordeal spoke of hysteria and panicked evacuations.
The false alarm sparked recriminations, with state officials apologising and President Donald Trump’s response called into question.
It was a mistake by an employee at Hawaii’s Emergency Management Agency (EMA) who “pushed the wrong button” during procedures that occur during the handover of a shift.
Mobile phone users received the message at 08:07 (18:07 GMT): “Ballistic missile threat inbound to Hawaii. Seek immediate shelter. This is not a drill.”
The alert was corrected by email 18 minutes later but there was no follow-up mobile text for 38 minutes, the Honolulu Star-Advertiser reports.
The alert system is in place because of the potential proximity of Hawaii to North Korean missiles.
In some cases panic, a dash to a protective bathtub or hiding under manholes. In others, a resigned acceptance, thinking that staring at the beauty of Hawaii was not a bad way to go.
Hassan Deen, a student at Hawaii Pacific University, told the BBC the alert sparked a frenzy and he was locked for 47 minutes with 29 other students in a room with rubbish bins.
Emma Hine, who is visiting Hawaii from the UK, told the BBC: “It was one of the worst experiences because I actually thought we were going to die. I’ve got a daughter – Chloe – back home in the UK and I thought ‘I’m not going to get a chance to say goodbye’. Everyone was genuinely terrified.”
Her son, Lewis, a disability campaigner, suffered a seizure due to stress.
Marathon runner Lucja Leonard said she had heard of children being “pushed into drainpipes to get them protected”.
“We all just huddled together and just thought – well, you know – if this is going to be the end I guess we’re in a beautiful place, doing something we love but – God – it was pretty scary.”
Danielle Smith told the Sydney Morning Herald she was on a beach when 50 phones went off.
“Everyone’s just looking around me going, ‘What do you do? What do you do?’.”
Her family was herded in to a local school. “We were just sitting in there and literally it was just silent, no-one was talking.”
The false alarm also threw golfers at the PGA Tour’s Sony Open at the Waialae Country Club into panic.
Steve Wheatcroft said “everyone is freaking out”, although Justin Thomas was more laid back, saying: “I sat on my couch and opened up the sliding door and watched TV and listened to music. I was like, if it’s my time, it’s my time.”
Hawaii state officials were profusely apologetic.
Governor David Ige said: “I am sorry for the pain and confusion it caused. I, too, am extremely upset about this.”
A federal investigation has started in the state and officials said they would work to ensure such a false alarm never happened again.
Vern Miyagi, administrator of the Hawaii Emergency Management Agency, also apologised for the “inadvertent mistake” but said the threat was still there. (Courtesy BBC)