The U.S. state of Hawaii was sent into a panic on Saturday when an emergency message went out to cellphones there warning of an impending ballistic missile strike.
The message told people to "seek immediate shelter. This is not a drill."
It turned out to be a false alarm -- someone "clicked the wrong thing," according to a spokesperson for the Hawaii Emergency Management Agency.
But the warning wasn't called off for almost another 40 minutes.
The false alarm has caused outrage in the state.
The governor has apologized, and officials have reportedly changed the procedure for issuing such a warning.
The possibility of a real missile strike has been more of a concern than usual in Hawaii lately as North Korea tests missiles that would put the islands within range.