Washington/Honolulu | An alert warning of a ballistic missile aimed at Hawaii today went off erroneously, sparking a panic in the US territory where fears of an attack by North Korea have heightened in recent months.

At around 8.07 am local Hawaii time, an emergency alert was sent to all cell phones in caps. “Ballistic missile threat inbounds to Hawaii. Seek immediate shelter. This is not a drill”.

About 10 minutes later, Hawaii Emergency Management Agency tweeted that there was no such threat. “No missile threat to Hawaii,” it said. The second emergency alert went out at 8:45 am.

“There is no missile threat or danger to the State of Hawaii. Repeat. False Alarm,” it said.

US Pacific Command in a separate statement said it detected no ballistic missile threat to Hawaii.

“Earlier message was sent in error,” it said.

It is unclear how or why the initial alert was sent out, and how many people received it.

Wireless emergency alerts are usually dispatched during critical emergency situations and are a partnership of the Federal Communications Commission, Federal Emergency Management Agency and the wireless industry.

Shortly after the false alarm, FCC chairman Ajit Pai said the commission was launching an investigation into what happened.

White House Deputy Press Secretary Lindsay Walters said President Donald Trump has been briefed on the state of Hawaii’s emergency management exercise.

The alert came when tension with North Korea has been at one of the highest points in decades, and when North Korean dictator Kim Jong-un has promised more missile tests and threatened an atmospheric nuclear test.

Less than two months ago, Hawaii reinstated its Cold War-era nuclear warning sirens amid growing fears of an attack by North Korea.

Democratic Congresswoman Tulsi Gabbard said the people of Hawaii “just got a sense of the stark reality of what a nuclear strike on Hawaii would be”.

“Over a million of Hawaii’s people were faced with the immediate reality of having 15 minutes to find a place to “take shelter,” wondering where do I go? What shelter is going to protect me & my family from a nuclear bomb? But there’s nowhere to go, nowhere to hide,” she said in a series of lengthy tweets.

“Everyone in America needs to understand that if you had to go through this, you would be as angry as I am — I have been talking about the seriousness of this threat for years,” Gabbard said.

The Congresswoman from Hawaii, Gabbard accused Trump of “posturing” and not taking nuclear threats from North Korea seriously and urged to begin direct talks with Pyongyang without preconditions.

“Donald Trump is taking too long. Now is not the time for posturing. He must take this threat seriously and begin direct talks with North Korea, without preconditions, to de-escalate and denuclearise the Korean peninsula. There is no time to waste,” Gabbard said.

“The people of Hawaii should never have had to go through this. The people of America should not be faced with this threat right now. We need peace — not political bickering. We have to talk to North Korea and find a peaceful path to get rid of this nuclear threat,” she said.