The bomb disposal team has been mobilised to Calderdale due to an ongoing incident at a property.
The disposal team has been called this morning from their base in Catterick, North Yorkshire.
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A spokesperson for West Yorkshire Police said: "Police are in attendance at a property on Swift Place, Sowerby Bridge after a reported hand grenade was found at a property.
"The Explosive Ordnance Disposal team has been called to examine the device."
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