An Alberta politician vacationing in Hawaii says the minutes she spent believing a missile attack was imminent were "really, really frightening."

Karen McPherson, who represents Calgary-Mackay-Nose Hill in the provincial legislature, was waiting for a conference call this morning when an alert appeared on her phone.

It stated there was an "inbound missile threat," warned her to take shelter and said it was not a drill.

Have never moved so fast in my life, had no idea where to go, but I was going there quite quickly. Now studying and have a plan —@MLA_Karen

It appeared to be the real deal <a href="https://t.co/tHUQlcJrLI">pic.twitter.com/tHUQlcJrLI</a> —@MLA_Karen

McPherson, who's staying in a condominium on the west side of Maui, woke up her friend and started driving for the tsunami evacuation route.

The two eventually discovered the alert had been sent by mistake and there was no inbound missile.

Calgarian Trish Hawley was vacationing in Maui with her daughter and two grandchildren, ages two and four, when she heard about the alert.

She was taking out the garbage when she saw people crowding into the building's parking garage. She asked one person what was happening, and they told her about the alert. She rushed upstairs to bring her family to safety.

'Shock mode'

"I went into shock mode. If this is it, this is it," she told CBC News.

When she realized it was a mistake, she said her first reaction was total relief.

"Everyone was trying to figure out what happened ... but it was the weirdest thing, it just went back to life as usual after," she added.

Officials in Hawaii have apologized for what they call "a mistake," and have vowed to ensure it never happens again.

With files from CBC Calgary