The Crest was cordoned off and a number of homes were evacuated as authorities, including units from the Tactical Response Group and Australian Army, removed the “explosive”.
Resident Jan Stott found the ball while gardening at her home where she has lived for 18 years. “I thought it was a cricket ball because it was reddish,” she said.
“I grabbed it and it was steel and solid so I took it inside and washed it off. That’s when I realised it looked like a bomb and should leave it.”
Cockburn councillor Phil Eva said he called police after inquiries from Ms Stott about what the item could be.
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READ NOWAuthorities, unable to work out exactly what it was from an image, believed it was a French grenade after examining it at the home.
But on Wednesday it was confirmed as an old shot put.
Ms Stott said the incident had generated more attention than she had anticipated. “When they came out they matched it to a French grenade so that’s what we thought it was,” she said.