Two children and an adult have been injured after a car mounted the pavement and flipped onto its side.

A child has been taken to Royal North Shore Hospital suffering from serious injuries following a crash at the corner of Archer Street and Victoria Avenue at Chatswood, an Ambulance NSW spokeswoman told 9news.com.au.

An elderly woman was also injured in the accident, and was unconscious when paramedics arrived at the scene. She is suffering from serious head injuries.

The family of a second child injured in the crash refused an ambulance, opting to take the child to their GP.

A man trapped inside a car at the scene has been freed by emergencies and is not injured.

Police said it is believed a driver suffered a medical episode.

More details to come.

Car flipped and Victoria Ave road closed outside Chatswood Chase. @Northshoretimes pic.twitter.com/oQp8GRsGsg

— Steve Hui (@iFLYflat) February 23, 2017

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