Last Updated Jan 13, 2018 3:03 PM EST
HONOLULU -- Hawaii emergency management officials said an alert sent to mobile phones and televisions warning of an incoming ballistic missile to Hawaii on Saturday was a false alarm. The emergency alert sent to cellphones said, "Ballistic missile threat inbound to Hawaii. Seek immediate shelter. This is not a drill."
Hawaii Emergency Management Agency spokesman Richard Repoza said it's a false alarm and that the agency is trying to determine what happened.
The alert broadcasted on television said: "If you are outdoors, seek immediate shelter in a building. Remain indoors well away from windows. If you are driving, pull safely to the side of the road and seek shelter in a nearby building or lie on the floor. We will announce when the threat has ended."
Sen. Brian Schatz, D-Hawaii, joined CBSN on Saturday and said the false alarm may have been caused by "human error." Schatz said Hawaiians are happy to be safe and "everything got canceled in a very short period of time."
"We're taking a deep breath knowing that it was a false alarm," Schatz said. "What I am hearing, and I don't know for sure, is that it was human error. Regardless of whether it was human error, a glitch or a hack, whatever it was, it is totally unacceptable."
Schatz said a local school suffered terrible anxiety from the alert. He said officials shepherd children into a locker room and had them shelter in place. "The state's emergency management system needs to do much, much better, and there needs to be better accountability."
Schatz urged residents to "hug your family, jump in the ocean and then on Tuesday ask your government what they're going to do to make sure this never happens again,"
Hawaii Rep. Tulsi Gabbard tweeted the alert and said she confirmed with officials that there was no incoming missile.
The false alarm comes amid heightened tensions with North Korea as the rogue nation continues to test ballistic missiles.
President Trump was briefed on the false alarm Saturday, a White House official told CBS News. The official said the alarm was "purely a state exercise."
The alert stirred panic for residents on the island and across social media.
Jamie Malapit, owner of a Honolulu hair salon, canceled appointments with his clients and closed his shop for the day. He told The Associated Press he was still in bed when his phone started going off for what he first thought was a tsunami.
"I woke up and saw missile warning and thought 'no way.' I thought 'No, this is not happening today,'" Malapit said. "I went from panic to semi panic and 'Are we sure?'"
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