Lynne Heraghty allowed herself a little laugh when she found an unusual metal object among the weeds of her back garden.

"Oooh, I've found a bomb," she joked, tapping it with her trowel.

But once she had knocked off the mud, Mrs Heraghty realised she really had found a grenade - causing a stir in Newmarket Road, Redcar, east Cleveland, on Sunday.

The mother-of-two said: "I had been digging up a concrete path and was clearing away the rubble when I noticed this strange object.

"I tapped it with my trowel, which makes me shudder to think about now. Then I realised it was a grenade, albeit badly corroded.

"I used to work in a munitions factory, so I saw it for what it was straight away."

The police took the grenade away and it was diffused by Army bomb disposal experts.

It is thought the grenade, made in 1936 for the British Army, may have been stored in an allotment shed which once stood near her garden.