Melbourne teen critical after being hit by car while crossing highway

A 14-year-old boy is fighting for life after being hit by a car while crossing a Melbourne highway overnight.

The boy was walking across the Western Freeway at Brookfield with three friends just after 11pm last night when he was hit by a black Kia 4WD.

The 47-year-old driver of the car stopped to help the boy. She and her young son were uninjured in the collision.

The boy, from Melton, was airlifted to the Alfred Hospital in a critical condition.

Police wish to speak to the teens who were with the boy when he was hit.

Outbound lanes of the Western Freeway have been closed between the Coburns Road and Hopetoun Park Road interchanges and delays are expected.

Anyone who witnessed the crash is urged to contact Crime Stoppers 1800 333 000.