What would you do if you had 15 minutes left to live?

What would you do if you were told you might only have 15 minutes left to live?

That thought went through the minds of many Kiwis holidaying in Hawaii this morning after they received an emergency alert on their mobile phones warning of a ballistic missile threat.

It was later made clear the message was false - it was accidentally sent out by the US state's Civil Defence organisation.

One Kiwi couple filled a bath, another woman grabbed her money and passport and was ready to flee.

Takapuna teenager Emma Bullock, who is on holiday in Hawaii with her family of five, said that when the alert went out, she did not think she was going to make it to see in her 18th birthday tomorrow.

"I felt sick and woke up all the family before rushing and packing my bags. Outside, there were locals just going for walks - little did they know the imminent danger of a missile.

"Twitter eased our worries before a long ... 40 minutes when the official alert said it was a 'false alarm'. I turn 18 tomorrow and really thought I wasn't going to make it! Hopefully the civil defence can get their alerts right next time."

Wellington woman Jane Woodrow, in Oahu, woke up to the message coming through on her husband's phone. So they filled a bath.

"I have to say that in that moment you do stop and think 'what do I do'.

"My husband filled up the bath tub and then along with our daughter we thought about what to do."

Kaye Bromley, from Wellington, told the Herald she woke up when her phone started humming and started grabbing up their personal possessions.

"I grabbed passports and money and then my husband came in from the gym saying they had been told to evacuate. We grabbed the kids and followed staff instructions to shelter in the basement of the hotel.

Emily Moore, of Auckland, said on Facebook it was the "scariest moment of my life. That was not fun, everyone was in so much despair".

Kiwi Mike Maloney ran from the poolside at the Hilton to wake his teenage sons up. He said they were "absolutely terrified" and wanted to come home immediately.

Kiwi Natalie Kane, who was staying the Waikiki Hotel in Hawaii, said the message freaked locals out and said children were in tears and families were running from the beach to find their loved ones.

"One man was in the bath tub with his daughter and family praying."

Petra Kostek had been honeymooning with her husband for the past week. They were due to fly out from Trump International Hotel Waikiki. They kept packing their bags, not knowing what else to do.

"People on phones crying, desperately running around and trying to find out what to do, people with kids saying they are going towards the mountains and that we should go far away from people and city too."

Dale Matravers had just stepped off the bus at the Waikele Premium Outlets with his wife and two children when the alert came through.

He said the local he was speaking to suddenly said he had to go and wished the family good luck.

Locals in Hawaii have described how they were faced with the decision about which family members to spend their last moments on earth with. One father said he chose to drive to his two youngest children because it was the largest grouping of his family, leaving his wife and oldest son alone.

Another mum tweeted that she could not leave work so called her son to wake him and tell him she loved him and stay inside. "When he asked, what's happening ... I could only say, "It'll be OK." She said it was a 45 minute drive to get home so she would not have made it anyway.