Belfast siren: Mystery noise caused by small Harbour Estate fire

Cranes in Belfast
The siren was caused by a small fire in the Harbour Estate

A loud siren heard across Belfast on Saturday morning was triggered by a small electrical fire in the Harbour Estate.

The Northern Ireland Fire and Rescue Service (NIFRS) confirmed that four fire engines attended an incident on Airport Road West.

It was reported at 08:48 GMT and resolved by 10:20 GMT.

The noise caused confusion among residents, with some on social media comparing it to an air raid siren.

"Anyone know why there's an air raid siren going off in Belfast for that seems like an eternity this morning?" a user wrote on X, formerly Twitter.

Another user said: "Should we be worried that the air raid sirens is going off in Belfast?"

Earlier in March the owners of a football stadium in Londonderry apologised after a late night faulty fire alarm kept local residents awake.

People living near the Ryan McBride Brandywell Stadium, which is home to Derry City FC, said they were growing increasingly frustrated with false alarms sounding at the ground.

One householder told BBC NI the alarm had gone off at least three times in the past year.

Last year a persistent night-time hum was reported by Omagh residents.

Alliance Party councillor Stephen Donnelly said he had been contacted by people in the Tamlaght Road area in late October, but there were also reports of the mystery noise from other parts of the County Tyrone town in the weeks that followed

Mr Donnelly said people had described it as "a persistent buzz or hum" distinct from more common noise such as traffic.

Many people reported problems sleeping because of the noise pollution.

A phenomenon known widely as "the Hum" has been reported across the globe over the past five decades, including in the UK, North America and Australia.

Some people have attributed such 'Hum' noises to farm or factory machinery, while others have subscribed to more outlandish conspiracy theories such as flying saucers.