An 18-year-old boy was rushed to hospital after having to fight another youth who allegedly tried to hijacked his car when the teenager entered his home in the east of Adelaide.
Residents near the corner of Lindsay St and Highland Ave in Rostrevor made multiple calls to police when a fight broke out between the victim and the accused on Wednesday night.
Police in South Australia say the 18-year-old suspect approached the 18-year-old driver as he got out of his car, hit him several times and demanded the car.
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The young victim fought off the accused but suffered head injuries, police said.
The 18-year-old suspect was found allegedly armed with a knife and arrested.
Police said the 18-year-old local man has been charged with aggravated robbery, assaulting police and unlawful interference.
He was refused bail by police and is expected to appear in the Adelaide Magistrates Court on Thursday.
