White House reported that US President Donald Trump has been briefed on the situation, calling it an "emergency management exercise."
Earlier, the Associated Press cited local officials as saying that an alert over a ballistic missile threat "inbound to Hawaii" was a mistake.
The alert reportedly urged residents to seek shelter, saying that "this is not a drill," causing panic, when it was received by people via their cellphones on Saturday morning.
"The President has been briefed on the state of Hawaii's emergency management exercise. This was purely a state exercise," White House spokeswoman Lindsay Walters said later.
HAWAII — THIS IS A FALSE ALARM. THERE IS NO INCOMING MISSILE. THE ALERT WAS SENT OUT INADVERENTLY. I HAVE SPOKEN TO HAWAII OFFICIALS AND CONFIRMED THERE IS NO THREAT. pic.twitter.com/hwRGct2aTa— Rep. Tulsi Gabbard (@TulsiPress) January 13, 2018
US military's Pacific Command announced that it had "detected no ballistic missile threat to Hawaii," adding that the text message warning sent earlier was an "error."
The alert comes just over a month after the US state of Hawaii has resumed its nuclear warning tests since the end of the Cold War due to North Korea's missile launches.
In his New Years Day address, North Korean leader said that US mainland is "in our nuclear strike range," a statement that has prompted harsh response from US President Donald Trump, who, in turn, noted that he has a "much bigger & more powerful" nuclear button.