The Piece Hall was built between 1775 and 1779 as a market for the display and sale of pieces of worsted and woollen cloth, and survives today as a landmark of Halifax. The Brighouse Echo, in a 2020 Halloween list of Calderdale's most haunted places, says it is haunted by market men who were murdered there.
That is the whole of the claim in the source. No victims are named, no dates are given and no sighting is described. The article does not say whether the murders are recorded in court or parish records or are part of the building's folklore.
It is included as a thin traditional report so that the Piece Hall is not missing from the Calderdale register. Anyone with a named case, a date or a primary source for a killing in the hall should treat the story as unverified until one turns up.
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