My phone rang. It was dad.

“Hi Dad, what’s up?”

I had actually spoken to him about 45 minutes earlier so it was unusual that he was calling back.

“Mum thinks she’s found an unexploded bomb in the garden.”

“What!”

“She’s on the phone now to the police…”

Mum is a keen gardener, and she’d been out digging in the flower beds of their back garden.

“Well tell her to stand back away from it. Don’t disturb it!”

Dad sounded both anxious and excited at the same time. Misplacing his glasses for an hour earlier that morning had been enough of an ordeal.

As it happened, I was now quite concerned as well.

He continued, “She’s just asking the police what to do. They want her to take a photo of it.”

Mum has a smartphone and knows how to take photos with it. Fortunately, I’d recently reminded her how to attach photos to an email.

“Just make sure you don’t touch it. Perhaps put a ruler in the earth nearby for scale.”

Dad, a keen viewer of TV crime dramas, thought that was a good idea and started looking for a ruler.

“What does the bomb look like?”

This is where I first got a mention of concrete. That didn’t sound like something you’d find in a bomb or other unexploded ordnance. But I’m not an expert. I’ve seen the old Thames TV show Danger UXB and that’s about the extent of my bomb-defusing knowledge.

I tried to persuade dad that mum should not continue gardening in another bit of the garden while they waited for the bomb squad or police to come around. Dad was slightly amused at the notion that mum’s beloved garden might get blown up. He’s not a gardener. I pointed out that any explosion may well take out part of the house too. This was a less amusing prospect for him.

“After mum’s emailed her photo to the police, get her to send me a copy too.”

When I opened the photo a few minutes later, it didn’t look exactly like a bomb, but definitely looked like it could have been cross section of a shell or something. It was round, and there was a central section. But then, I don’t really know what a 75 year-old bomb might look like.

My parents live quite close to the cliffs in North Norfolk. On a nearby hill are the remains of various WWII-era gunning emplacements. The coastline was always considered a risk for German invasion, and the local town was certainly bombed by the Luftwaffe. Plus there was a Y-station on the hill, where radio receivers intercepted encrypted German signals to send through to the code-breakers at Bletchley Park. Certainly a target, it wasn’t impossible that there was something dangerous buried deep in the garden.

The house is one I’ve been visiting since I was a small child. My grandparents bought it, I believe in the sixties, as somewhere to retire to. My parents inherited it, and they too retired there. I know the garden well. Could there have been an unexploded device there all that time?

I phoned mum back after looking at the photo.

“I’m not sure that it’s a bomb. If anything, it looks like a home-made device to support a whirligig.”

I was talking about those rotary washing line things – with a pole that you slot into the ground and unfurl to hang your washing out on. Mum uses such a device, but it’s in a different place in the garden.

“The metal outer could be something like a paint can or small bucket. The inner a piece of pipe. Could grandad have made something like that for grandma? Filling the space with concrete?”

My grandfather had spent time working for the family building firm. I wouldn’t describe him as a master craftsman, but he made things, and wasn’t afraid of a bit of DIY – especially if it saved him going out and having to buy something.

Mum conceded that perhaps that was right, but she wanted me off the line for when the police phoned back.

I waited nervously, posting the pictures mum had sent on Twitter. Did I have any bomb-defusing expert followers? (No, you’ll be amazed to hear. It turns out I don’t.)

A little later I got a call back from mum.

A nice policewoman had been around and it was indeed a paint can filled with concrete. She’d helped mum dig it up.

I may have been slightly smug that my suggestion had been spot on. The location of it wouldn’t make sense for a clothes airer in 2020 because mum has reworked the garden quite a bit. But it perhaps would have done in the sixties or seventies when the lawn ran almost right to the fence, and there wasn’t space for flower beds, or trees to block you opening out a clothes airer.

Mum was apologetic to the policewoman, sorry for wasting her time. But she’d said that it was one of the more enjoyable things she’d had to do recently.

I consoled my dad. Now he wouldn’t be likely to appear with Stewart White on BBC Look East, his favourite news programme. The blowing up of a wartime bomb on the nearby beach would surely have got some coverage. Finding a paint can full of concrete buried in your garden was unlikely to.

But at least my parents had not been blown up.