The Leopold Street resident woke this morning to find a box, containing heather and perched on a front window, had suddenly vanished.
In its place was a plastic box filled with new heather.
The resident, who has asked not to be named, said she believed the box was stolen overnight and may have been swapped with one belonging to another house.
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She said she had checked the whole street, and didn’t believe the box - which cost about £50 - had been broken and replaced because there was no earth visible.
She added: ‘It has really ruined my day.
‘Either someone stole it, but why replace it? They broke it and felt guilty, or someone is trying to scare me.’
She is now asking local residents to keep an eye out for the window box.
Have you seen the window box, or has yours been mysteriously swapped? Contact the newsroom by calling 02392 622114 or emailing [email protected]