Elderly woman dies after a hit-and-run

An elderly woman has died in a hit-and-run on a busy highway in north Sydney.

She was knocked over, allegedly by a taxi, while trying to cross the Pacific Highway at Crows Nest on Tuesday morning.

The driver didn't stop after hitting the woman, who is believed to be in her 80s, police say.

The south-bound highway is closed between Falcon street and Myrtle street, while one north-bound lane is also closed.

Paramedics were unable to save the woman, who died at the scene.

A crime scene has been established and police are appealing for witnesses to come forward.