The source of a huge bang that shocked residents of Port Gardens on Sunday night remains a mystery, with police turning up no leads. 

Hundreds of comments on social media appeared immediately after the bang, which was heard at about 10:50pm on April 5 by residents in the Port Gardens area, including St Crispin’s Avenue, Brolga Street, Ulysses Avenue, Four Mile Beach and many others. 

A flash of light was also reported in the sky. 

Speculation ranges for the cause of the bang, including a blown transformer, car backfiring or large firework. 

One person claimed to have fired a rifle at a crocodile in Mowbray but her story was disputed by other commenters. 

Police said there was ‘no evidence of an explosion’ and no further leads. 

Did you hear the bang? 

Know anything? Have a theory on what it was? Leave a comment below.