Weekend home renovations came to an alarming halt for a resident on the New South Wales South Coast after he discovered a 30-centimetre-long mortar shell.

Plumber Elliott Doughty moved into his new home in Bulli last month and was digging underneath a concrete slab in his backyard on Sunday afternoon when his shovel hit something unexpected.

“I didn’t know it was a bomb at first, but I hit pretty hard,” Mr Doughty said.

“Nothing happened — thank God — so I assumed it was safe to move out of the way.”

Intrigued by its torpedo-shaped appearance, Mr Doughty carried the mortar over to a nearby tap to rinse off the dirt.

Man with facial hair holds a baby around his neck, brunette woman holds camera while standing in front of ocean.

Elliott Doughty, his wife Finn and daughter Sunny moved into their home in Bulli one month ago.(Supplied: Finn Hutchinson Doughty)

“Once I could really see what it was, I took extra caution,” he said.

“In hindsight, I probably shouldn’t have been fiddling with it like I was.”

Finn Hutchinson Doughty, Elliott’s wife, said she stayed clear of her husband as he held the mortar shell with his bare hands.

Mr Doughty admits he was wondering what to do with the mortar and, before dialing emergency services, consulted a neighbor for advice.

“I wasn’t going to put it in the red bin.”

Two shovels lean up against wall, dirt hole in ground, bits of concrete next to holes.

Elliott Doughty says he was digging a space for drainage pipes when he discovered the mortar.(ABC Illawarra: Brooke Chandler)

A Police Bomb Squad, Bulli Fire and Rescue, and Australian Defense Force (ADF) personnel arrived at the Organs Road property and blocked off the traffic to conduct their investigations.

“We haven’t been in this house long, so I didn’t want to make a fuss,” Mr Doughty said.

“It was actually embarrassing because we had emergency services lining the street and people were wondering what was going on.”

Safe to transport

A mortar is a lightweight, portable, muzzle-loaded weapon that can launch explosive shells with a 5-meter explosion radius. They were most commonly used in World War I.

A group of men crowd in Bulli street, wearing their emergency service uniforms, all are looking at something, nighttime.

Emergency services, including Australian Defense Force personnel, screened the mortar for possible detection activity.(Supplied: Elliott Doughty)

Mr Doughty and his wife’s anxiety were put to rest as ADF crews X-rayed the mortar and confirmed there was no active fuse.

“There was talk of [the ADF] going to blow it up on the beach,” he said.

“I thought the cops were pretty excited about it and I was pretty excited about it too.”

In a statement, a defense spokesperson said ADF personnel responded to a call made by police.

“Australian Defense Force personnel attended and identified the mortar was degraded but safe for transport.

“The mortar will be disposed of using routine measures.”

Memorable Sunday afternoon

Mr Doughty said he was still trying to process his discovery of the mortar and large-scale emergency services response.

Hand pointing to mortar shell under x-ray screen, dark all around.

ADF personnel used X-ray technology to screen the mortar and confirmed it was safe to transport.(Supplied: Elliott Doughty)

“I was looking forward to going for a surf … but things kept getting in the way,” Mr Doughty said.

“Didn’t think a bomb would [get in the way of a surf]. It’s pretty out of the blue.”

The ADF has not contacted Mr Doughty with any further details about the discovery since it was transported away from his Bulli residence.

“But the general consensus is it was either someone’s souvenir back in the day, a previous owner had forgotten about it or got rid of it by burying it,” he said.

“I was glad to watch it being driven away from my house.”

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