The 20-year-old man was arrested on Synnot Street in Werribee on Monday. Credit:Jessica Karasmanis "The potential of the attack is catastrophic. This is a person who has expressed an intention to try and kill as many people as he could. It's horrendous," Mr Patton told reporters on Tuesday. "We have been monitoring him for a very lengthy period of time." The family's home is being searched by police after his place of work, a computer business in Footscray, and a relative's home in Meadow Heights were inspected on Monday. Father says son is 'very innocent'

On Tuesday morning, Ali's father spoke briefly to media from the front yard of his brick veneer home. The 20-year-old Werribee man is taken into custody. Credit:Victoria Police He denied his son would have harmed anyone, and then quickly went back inside, where police are still searching. "He's very innocent," the man's father said. Police at the accused man's family home in Werribee on Tuesday. Credit:Jason South

Sheikh Isse Musse from Werribee Mosque said he knew Ali's father well, seeing him at the mosque several times a week. He saw his children less often. His father had worked exceptionally hard as a taxi driver to provide for his children, and his wife took care of the home. The suspect was allegedly planning to shoot and kill as many people as he could in Federation Square. Credit:Victoria Police "He's a very hardworking man, always on the road," Sheikh Musse said. Police seized several bags of evidence from the family's home, including a large framed picture.

Victoria Police deputy commissioner Shane Patton (left) and AFP assistant commissioner Ian McCartney. Credit:Justin McManus The couple had moved to the home because they did not feel safe in the government housing they had been provided after arriving from Somalia more than a decade ago. They were worried about drugs in the area, particularly. Fireworks over Melbourne CBD on New Years Eve. Credit:Melbourne City Council "They wanted the children away from that area," Sheikh Musse said.

The couple had toiled to ensure their children could go to the private Al-Taqwa College, an Islamic school in Truganina The college declined to comment on Tuesday. A neighbour said the "beautiful family" had lived in the house for at least a decade. "They're just lovely, everyday, people," she said. The man's father had apologised to her on Tuesday morning for the hassle regarding the arrest.

"I believe he didn't know anything," the neighbour said. "I just felt like he was more heartbroken." The neighbour arrived home on Monday afternoon after picking up her daughter from school to find eight to 10 police cars lining the street. "It was quite frightening." The 20-year-old man was arrested on the corner of Synnot and Bridge streets in Werribee, which is a shopping area one street behind the suburb's main retail strip, just after 3pm on Monday. 'A very, very quiet boy'

Warsame Hassan, the owner of Wix Computers in Footscray where the accused man worked, said 10 to 12 police officers stormed the store on Monday and took a computer, a hard drive and CCTV footage from the shop. Mr Hassan described the man as a quiet boy who did work experience at the store for about two to three hours at a time, sometimes one or twice a week, sometimes less. "He was a very, very quiet boy. He never spoke much. It was a shock," Mr Hassan said. He said he had met the young man's father at the Virgin Mary mosque in Werribee. His father wanted him to do work experience so he could go to university next year and eventually get a job in the computer industry.

Al-Qaeda guidebook and other extremists The young man was in possession of an al-Qaeda guidebook on how to carry out terrorist attacks and is an Islamic State sympathiser, police allege. "He has accessed documents produced by al-Qaeda Arabian Peninsula ... a guidebook in respect to how to commit a terrorist act and also how to use firearms, guns and handguns and rifles," Mr Patton said. "He is associated with other persons in the Victorian extremists community ... it is a very small community of extremists. "This is a person who would become particularly energised when overseas events occurred. He expressed a great amount of interest in committing an attack himself."

Mr Patton reassured the community the man was acting alone and no threats were ongoing. "We are not looking for any other suspects," he said. Authorities are still investigating how the young Werribee man became radicalised, Mr Patton said. Police do not believe he is linked to any mosques in Melbourne. They would not reveal if his family or friends knew of his intentions.

This is his first time in custody. He is expected to be charged later on Tuesday with engaging in acts in preparation for a terrorist offence and collecting documents to facilitate a terrorist act. Victoria Police, Australian Federal Police and ASIO were involved in the investigation that resulted in the young man's arrest. No ongoing risk Police Minister Lisa Neville said police were continuing their investigation, but had foiled another threat.

"Absolutely police were aware of this very early and had been monitoring," she said. "There was never any point in which there was a significant risk. I can absolutely assure Victorians that this has eliminated the risk." Ms Neville said Victorians should be confident to make plans for New Year's Eve. "There is no ongoing risk to the Victorian community." An estimated 450,000 people flock to Melbourne's CBD to ring in the new year in the city.

Security has been ramped up in recent years, particularly last year after police foiled a Christmas Day terror plot. Hundreds of uniformed police swarmed the city last New Year's Eve, particularly near St Paul's Cathedral and Flinders Street Station which were both targets of the Christmas terror plot. Specialised squads including water police, mounted branch, operations response unit and air wing were deployed across the state.