A grandmother in Britain has told of her terror at opening a parcel she had been expecting - only to find she had been sent a police machine gun.

Catherine Roots had been expecting a horse harness to be delivered to her home in Winfrith, Dorset.

But she got a nasty shock when she saw a black Heckler and Koch weapon staring back at her.

The package was delivered by mistake and should have been sent to firearms officers at a nearby police headquarters.

Police later explained a gun supply company made a mistake with the postal code when they sent it to Dorset Police HQ in Winfrith near Dorchester.

Instead of sending it to DT2 8DZ, a clerk wrote down Root's postcode, which differs only by a single letter.

"I was absolutely and totally shocked, and petrified," Roots, who is in her 50s, said. "If it had got into the wrong hands the consequences wouldn't bear thinking about."

Roots was later told the weapon was in fact a realistic-looking training gun that fires infra-red beams.

Assistant chief constable Adrian Whiting, of Dorset Police, said: "Because this item isn't actually a firearm it is lawful for the company, the suppliers, to use a courier as they did."

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