Teenager arrested over attack on four elderly people in Sydney's south-west A teenager has been arrested for attacking four elderly people in Sydney's south-west. The 19-year-old man got into an argument with an 85-year-old man about 6pm on Saturday outside a Bonnyrigg home. The elderly man had nearly hit the teenager, who was on a scooter, while reversing out of his driveway. After initially leaving the area, the young man returned and assaulted the elderly man as well as his three friends, a 75-year-old woman, a 61-year-old man and an 87-year-old man. The woman and the 61-year-old man were taken to hospital with minor injuries. The other two had minor cuts on their elbows but did not need medical treatment. The 19-year-old was arrested about 4.40pm on Sunday at Busby and taken to Fairfield Police Station.