Police are investigating an overnight assault on a man at a Lismore taxi rank.

Police from Richmond Local Area Command attended Keen Street, Lismore, about 8.40pm yesterday (Thursday 23 October), after receiving reports of a man with a severe facial laceration following an assault outside a nightclub.

He was taken to Lismore Base Hospital for treatment of the injury.

A crime scene was established and officers conducted inquiries at the scene.

Witnesses have told officers the man had been involved in an argument with a woman when she allegedly struck him with a ceramic mug, causing the cut to his face.

The woman and another man then left the scene in a taxi before police arrived.

She has been described to police as being of Aboriginal appearance, aged in her mid to late 20s, 160cm tall with dark complexion, black hair and brown eyes.

Inquiries are continuing and police are appealing for witnesses to the incident to come forward.

Anyone with information that might assist investigating officers is urged to contact Lismore Police Station or Crime Stoppers on 1800 333 000.