Residents across Cardiff and the Vale of Glamorgan reported hearing a "big bang" on Thursday evening. People living in Caerau, St Fagans, Culverhouse Cross, Cowbridge, Barry and Gabalfa reported hearing a loud noise from their homes on Thursday, May 4.
Speculation arose among residents as to the cause of the mysterious noise with ideas from thunder to terrorist attacks. However a spokesperson for South Wales Police says that they know what was "most likely" the cause for the disturbance.
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