Amone, whose full name is Talatau Junior Amone, was arrested at his home on Thursday morning and charged with reckless grievous bodily harm in company, damaging property and intimidation.

Court documents seen by the Mercury said the victim parked his vehicle legally on the nature strip in Vermont Road before starting work on a two-storey building on the morning of Tuesday, November 15.

Amone's father and co-accused, Talatau 'Dal' Amone, allegedly came out of his home and walked towards the victim's car, parked across the road, then began taking photos of it.

From the building's roof, the victim said: "Why are you taking photos of our car?" several times, to no response, and the senior Amone returned home.

But a short time later he allegedly returned, reached through the open driver's side window of the victim's vehicle and snapped something off - believed to be the indicator toggle - before discarding it on the road and returning home.

About 11.20am, the senior Amone allegedly came out with his son - armed with a hammer - and an unknown male.

Police alleged the younger Amone and the unknown man then jumped on the roof of the vehicle, causing major damage to the roof and smashing the windscreen.

The victim called triple-0 for help, while the two Amones and the third man allegedly climbed up a ladder onto the roof where he and his colleague were working.

Junior Amone allegedly swung the hammer at the victim, who fled and jumped onto the roof of the neighbouring property.

Police alleged Amone pursued him, continuing to swing the hammer.

The victim reached the edge of the roof and, unable to go anywhere, turned to face Amone.

Amone allegedly lashed out with the hammer again and the victim stepped backwards, causing him to fall off the roof.

He grabbed guttering in a bid to save himself, but it gave way.

The victim fell to the ground, hitting an air-conditioning unit on the way down.

From the roof, Amone allegedly yelled: "Get the f---ing c---".

Police alleged the elder Amone and the unknown male climbed down the ladder, followed by the victim's workmate, who removed the ladder to stop Junior Amone from getting down.

A dog unit officer arrived on the scene a short time later and saw Amone on the roof with a hammer, before he moved out of sight.

The unknown male ran behind the neighbouring property and the victim, fearful upon seeing him, managed to get himself off the ground and jump into the backyard of an adjoining property, before fleeing down a laneway.

Amone and the other man allegedly chased him, before he sought refuge in a home. There he collapsed and called triple-0.

Meanwhile Amone and the unknown man did not return to the Amone home; police said CCTV captured them running on Barbara Avenue towards Minnegang Street.

Dal Amone returned to his home and told police he had been to the pool and was unaware what had happened.

Paramedics took the victim to hospital.

He and his co-worker allegedly identified Junior Amone as the main aggressor.

Police established crime scenes, including one at the Amone home.

However, they said that while the home was covered by high-quality CCTV cameras, a search failed to uncover the system's hard drive and it appeared it had been unplugged.

In an interview with police after his arrest on Thursday, Amone declined to comment.

The 20-year-old did not appear at Wollongong Local Court on Thursday afternoon when his matter was mentioned, nor did he apply for bail and bail was formally refused.

He will return to court on Friday.

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