Mr Chadd wasn’t home at the time of the attack but said his neighbours were woken by the noise about 2am on March 10.
Neighbour Sally Palmer said she was startled by the blast and ran out to the scene with towels in fear of someone being hurt from what she believed was a car crash.
‘The blast was similar to a car hitting a wall,’ she said.
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READ NOW‘When I got out the front there was no car but I could smell burning which was coming from Jim’s limestone letterbox.’
She added that the front of the letterbox was blown ‘right out of the garden’ and sheared leaves off trees.
Ms Palmer said there was a witness who saw a car stop out the front of Mr Chadd’s house before the blast went off.
According to Ms Palmer, the witness saw one of the four occupants in the dark blue low-lying car get out of the car and place something in Mr Chadd’s letterbox. The person got back in the car which was then driven off.
Ms Palmer said one of the occupants was described as ‘portly with slightly balding dark hair’.
Mr Chadd said the incident had been reported to police and forensic officers had inspected the area.
‘Not only is it unlawful but quite un-Australian,’ he said.
Morley Acting Senior Sergeant Mark Folkard said the police were aware of the incident and believed it was a one-off.
He said there was no way of preventing these sorts of attacks but if a similar incident happened to others in the future they should leave the scene untouched until police got there.
Snr Sgt Folkard encouraged people to contact Crime Stoppers on 1800 333 000.