An elderly woman has died days after a serious head-on crash that also injured a man and a boy in Sydney’s south.

Emergency services were called to the Princes Hwy, north of Tom Ugly’s Bridge in Blakehurst, after a sedan and SUV collided at about 2.30pm on Saturday.

The 44-year-old driver of the SUV and his passenger, a 13-year-old boy, were treated by paramedics at the scene before being taken to St George Hospital in a stable condition.

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The trapped sole occupant and driver of the sedan was rescued by the Fire and Rescue NSW team, using the jaws of life.

The 87-year-old woman was rushed to hospital in a critical condition, but police were told at about 8pm on Wednesday that she had died.

“An investigation into the circumstances surrounding the crash continues,” police said.

“A report will be prepared for the information of the Coroner.

“As inquiries continue, anyone with information or dashcam footage is urged to contact Crime Stoppers.”