It should have been a routine, internal test carried out during a shift change at the Hawaii Emergency Management Agency just after 8am.
Instead, according to official explanations, somebody clicked the wrong thing at the wrong time, sending warnings of an incoming ballistic missile attack to mobile phones across Hawaii.
“BALLISTIC MISSILE THREAT INBOUND TO HAWAII. SEEK IMMEDIATE SHELTER. THIS IS NOT A DRILL,” it read.
The result was 38 minutes of panic in state already on edge because of growing tensions between the US and North Korea.
Joseph Kira was at home with his children when the alert came. His wife was at the gym.
“My wife was going ballistic,” he said. “At that point, you just pray and find God, I guess.”
Hawaii is already used to dealing with deadly disasters such as volcano eruptions and earthquakes. During recent months residents have been coming to terms with the island chain’s location within range of North Korea’s growing nuclear arsenal.
Last month the state reintroduced tests of its warning sirens, something not done since the Cold War ended.
Hawaii’s 1.4 million population knows what to do when the warnings are triggered – seek shelter immediately.
Customers at coffee shops dived under tables or tried to find shelter at home. There are few basements and many people could only huddle in garages.
Hotels packed with tourists seeking out winter sun had to deal with thousands of guests unsure where to turn.
Professional golfer Colt Knost, staying at Waikiki Beach during a PGA Tour event, said the lobby of his hotel filled with panicking families.
“Everyone was running around like, ‘What do we do?’” he said.
It took seconds to spark the panic, but state officials already knew there was no attack.
The alert was triggered at 8.07am. By 8.10am, Maj Gen Joe Logan, state adjutant, had already conferred with the US military’s Pacific command and knew there was no attack.
But there was a problem. The warning was out there, in the sort of blunt language that could not be ignored. It was one thing to send alerts, quite another to recall or correct them.
At 8.13am the next best thing happened: the danger warning message was cancelled, meaning it would not be rebroadcast to phones that had not yet received it.
No one across the Pacific Ocean islands knew it yet. They were still hunting for safety or saying their goodbyes to loved ones.
Cellphone networks jammed and vehicles were abandoned on the H-3, a major highway north of Honolulu, where drivers ran for the safety of a nearby tunnel.
Jocelyn Azbell said she was among guests at her Maui hotel who were “herded like cows” into the basement.
“Hawaii is beautiful,” she told CNN. “But it's not where I want to die.”
To add to the rising tide of panic, 12 of the 386 emergency sirens started to sound – even though they were not part of the text warning system.
Diane Pizarro, who was at home with her family, told the Honolulu Star Advertiser: "That gave more credibility to the text."
Sara Donchey, an American TV reporter based in Texas, was in Honolulu visiting her family when she woke up on Saturday to a string of messages on her phone warning her of the danger.
“Honey take shelter, I love you,” read one of her messages.
“This was my phone when I woke up just now,” she posted on Twitter. “I'm in Honolulu, #Hawaii and my family is on the North Shore. They were hiding in the garage. My mom and sister were crying. It was a false alarm, but betting a lot of people are shaken.”
Tulsi Gabbard, a Democratic congresswoman for Hawaii, said the reaction was natural at a time of heightened sensitivity.
“This is a real threat facing Hawaii, so people got this message on their phones and they thought: 15 minutes, we have 15 minutes before me and my family could be dead,” she told CNN.
The islands have recently begun holding “Are You Ready” drills, briefing the population on what to do in the event of a strike.
Even as people huddled in garages or sent last messages to loved ones, the authorities knew there was no missile.
Thirteen minutes after the mistaken text was sent the Hawaii Emergency Management Agency (Hema) managed to post Twitter and Facebook messages that it was all a false alarm, but it would still take another 25 minutes for a correction text alert to go out to phones.
Vern Miyagi, the agency’s administrator, said officials had to wait for authorisation from the Federal Emergency Management Agency to send out a retraction.
The apologies began even as tearful families were still coming to terms with what had happened. The inquest into how an erroneous emergency alert could be sent so easily – and be so difficult to be reversed – will last much longer.
“Today is a day most of us will never forget,” said David Ige, the state’s governor, at Diamond Head Bunker, the emergency command post from where the mistaken alert was sent.
“A day when many in our community thought that our worst nightmare might actually be happening. A day when many frantically tried to think about the things that they would do if a ballistic missile launch would happen."
Mr Miyagi offered more details of the mistake. An unnamed employee mistakenly pushed a button sending the alert rather than a button marked for testing. The employee then clicked through a safeguard, selecting “yes” when asked whether he was sure he wanted to send it.
Officials were quick to offer solutions to ensure such panic would not be allowed again. They promised to build a “cancellation template” to make it easier and faster to correct mistakes and immediately instituted a new system to ensure two people must sign off on future alerts.
The state legislature has scheduled a hearing for Friday.
Scott Saiki, the house speaker, said the system had failed miserably.
“Clearly, government agencies are not prepared and lack the capacity to deal with emergency situations,” he said in a statement.
Brian Schatz, a senator for Hawaii, tweeted that the false alarm was "totally inexcusable".
“There needs to be tough and quick accountability and a fixed process,” he wrote.
For residents, who now know what it is like to be told they have minutes to live, the result is lingering anger that a simple mistake too so long to fix.
“So this was the most terrifying few minutes of my LIFE!” Paul Wilson, a professor at Brigham Young University-Hawaii, wrote on Twitter. “I just want to know why it took 38 minutes to announce it was a mistake?!?”
Hawaii sends out emergency missile alert by mistake
North Korea says its nuclear missiles are ‘aimed at America’ only
[ Kim vows North Korea will mass-produce nuclear warheads and missiles ]