Two males, one armed with a knife, robbed the Z service station in Dublin St on Friday evening.
It is the latest in a string of aggravated robberies of dairies and service stations in Whanganui. Just two weeks ago dairies in Whanganui East and Castlecliff were targeted by armed robbers.
Detective Sergeant Glenn Toy said no-one was injured in the Z robbery. The offenders, whose ages are unknown, took tobacco and cash.
Police enquiries are continuing. Anyone who saw two males running from the service station along Pitt St toward Liverpool St at about 8pm on Friday is asked to contact Whanganui Central Police Station on (06) 349 0600.