Story highlights Nuclear warning test will be included as part of regular statewide siren test

An estimated 18,000 Hawaiians would be killed in a nuclear strike, state agency says

(CNN) Hawaii is taking those threats from North Korea seriously.

Starting Friday, the state will start monthly testing of a nuclear warning siren system aimed at alerting residents to an impending nuclear missile strike. It's the first such tests in the Aloha State since the end of the Cold War.

The test of the nuclear warning siren will be conducted during the monthly tests of the overall statewide warning siren system, according to the Hawaii Emergency Management Agency.

At 11:45 a.m. on the first business day of every month, a steady alert signal will blare from speakers for 50 seconds, followed by a 10-second pause and then a wailing "attack warning" signal for 50 seconds.

In the event of an actual attack, Hawaii's 1.4 million residents are expected to seek shelter immediately after hearing the attack warning signal. An emergency alert system will broadcast warnings on TV and radio as well.

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