Creepy nuclear siren sounds from Royal Navy's HMNB Portsmouth amid rain showers - why and what was it

An eerie nuclear siren sounded from the Royal Navy’s HMNB Portsmouth this morning.

The creepy two-tone siren was set off just before 9.30am, with an announcement being made beforehand. It has been known to be heard throughout parts of Portsmouth. It blared for just over one minute.

HMNB Portsmouth issued a social media statement this morning. They said: “Please note there will be a full test of the Naval Base’s nuclear emergency alerting siren at 0930 today which may be able to be heard outside of the base.

“It is a statutory requirement to test the alarm three times a year and this test is being conducted in agreement with Portsmouth and Gosport local authorities. The two-tone siren will be sounded for one minute for the test.”

The alarm is raised on the last Wednesday of February, June, and October, every year. These safety routines and procedures are a statutory requirement, outlined by Portsmouth City Council and Gosport Borough Council.

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