Asda's head office building was evacuated after a "suspicious package" was discovered.
West Yorkshire Police received reports of the item having been sent to Asda House, on Great Wilson Street in Leeds, at about 11:15 GMT on Monday.
An Army Explosive Ordnance Disposal team attended and carried out a controlled explosion on the package.
Emergency services continue to work at the scene, with roads around the building remaining closed on Monday evening.
Video footage from the scene earlier showed a bomb disposal device being wheeled out of the back of an Army truck towards the premises.

A spokesperson for Asda confirmed the building had been evacuated safely.
A West Yorkshire Police spokesperson said: "Motorists are advised to avoid parts of Leeds city centre for the coming hours due to the ongoing incident in Great Wilson Street.
"Nobody has been harmed as a result of this morning's incident and there is no wider threat to the public.
"Roads affected include Victoria Road, Meadow Lane, Neville Street, Bridge End and Great Wilson Street."
Some bus services in the city centre were impacted by the incident, along with an unconnected collision outside The Light leisure complex.

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