Police are hunting a knife-wielding offender who attempted to rob an Auckland mini-mart on Tuesday afternoon.

The man, wearing black clothes and a cap, presented a knife to the shop attendant at a mini-mart in Blockhouse Bay Rd, southwest of downtown Auckland.

Inspector Barry Smalley of the police northern communications centre said a window was broken during the incident but nothing was taken and nobody injured.

He said the offender ran away and police were seeking information to try and find him.