HONOLULU (Reuters) - Panic and confusion swept Hawaii on Saturday as a mistaken alert about a ballistic missile attack spread across the Pacific U.S. state, sending residents and tourists scrambling for shelter and questioning why an all-clear was not issued faster.

Students run for cover after an emergency alarm was sounded, at a carpark in the University of Hawaii, Honolulu, Hawaii, U.S. in this still image taken from social media video, January 13, 2018. JOE WALKER TWITTER / @_JoeWalker/via REUTERS

Rhonda Ramirez and Michael Sterling, both 56 and from Los Angeles, were staying at a hotel in the Waikiki tourist district when the state emergency agency issued the bogus alert at 8:07 a.m. HAST (1807 GMT).

Ramirez, a mortgage broker, “immediately started crying. I was thinking, ‘What could we do? There is nothing we can do with a missile,’” said Sterling, a law firm employee.

The hotel told guests to stay indoors and about 30 minutes later announced the all-clear.

“That seems too late,” Sterling said as he and Ramirez prepared to have breakfast at a restaurant.

Ikaika Hussey, 39, publisher of Summit Magazine and candidate for Honolulu City Council, was home with his children when he got the alert. They grabbed food and headed for a room with a rock wall, he said.

He blamed Hawaii’s status as a potential target on its being home to the U.S. Pacific Command and the Navy’s Pacific Fleet.

“Militarism is reducing, not enhancing, our security,” Hussey said by phone.

The false alert came amid high international tensions over North Korea’s development of ballistic nuclear weapons. The alert was not corrected for 38 minutes. Many in Hawaii learned it was false because of a tweet sent in the interim by U.S. Representative Tulsi Gabbard.

State Representative Matt LoPresti told CNN he and his family sought safety in a bathtub but wondered why nuclear alert sirens had not sounded.

“That was my first clue that maybe something was wrong, whether a hack or an error. But we took it as seriously as a heart attack,” he said.

Governor David Ige apologized for the mistake, saying it occurred when the system was being tested during a shift change at the Hawaii Emergency Management Agency.

Since the sirens did not ring out, work continued as normal at a post office in Honolulu’s Manoa district, said part-time postal worker Adam Goss, 32.

Puzzled friends contacted by Goss told him that they were hearing nothing more about any imminent attack.

“I think they should have put out another message right away, rather than for us to have to check Twitter for Tulsi Gabbard’s message it was a false alarm,” Goss said.