Emergency services were called to Hertford Street in Berkeley just after 11.30pm on Sunday, May 10, with reports an unregistered trail bike had collided with a car.

There they found a 17-year-old boy and his 16-year-old female pillion passenger, with serious injuries. They were both treated at the scene before being taken to hospital for treatment.

The male driver of a Toyota Aurion, stopped and tried to help the injured teens before he was taken to hospital for mandatory testing.

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The girl had not been wearing a helmet at the time and was thrown at least 10 metres down the road, suffering a life-threatening head injury. She died four days later in hospital.

Friends and family paid tribute to the victim online after her death, describing her as a "beautiful girl", as well as leaving flowers at the scene.

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The 17-year-old youth was arrested by officers from the Metropolitan Crash Investigation Unit on Saturday.

The accused was issued with a Court Attendance Noticed for dangerous driving occasioning death, and negligent driving occasioning death.

He is due to appear in a children's court on October 13.

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