An electric bike rider is fighting for her life in hospital after colliding with a hatchback.

The crash happened at the intersection of Alexander Ave and Bains Rd at Morphett Vale, in Adelaide’s outer southern suburbs, about 10.20pm on Monday.

The scooter rider, a 28-year-old woman from Morphett Vale, was critically injured.

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She was rushed to hospital where she remains fighting for her life.

The sedan driver, an 18-year-old woman from neighbouring Christies Beach, was not injured and is assisting police.

The road was closed for several hours as officers from South Australia Police Major Crash team investigated but have since re-opened.

Anyone who may have witnessed the crash is asked to contact police.