The others wore dark jackets and pants. One had a hooded jacket and the other wore a vest over his jacket. Scarves and hoods obscured their faces.
Mr Kirby said robberies tended to come in cycles and, over the past three months, there had been an increase in the number of robberies of dairies, shops and residential homes.
While some arrests had been made, including those responsible for brandishing a knife at the Rangitikei St store, others, like Saturday's robbery and two recent robberies of the Fitzherbert Ave Dairy, were ongoing investigations.
In particular, the increase in frequency of robberies of cigarette outlets had increased since cigarette prices had gone up.
However, Mr Kirby warned anyone contemplating such an offence as an easy, quick way to get cigarettes and cash that they would be caught and faced a maximum 14 years in prison.
As in the latest robbery, where two witnesses were in the shop at the time it was held up, Mr Kirby said people who found themselves in that situation were advised not to aggravate the situation.
If possible, they should take a good look at the offenders, taking in details of their clothing, voice and facial features - but only if they could do it safely.
Robbers were usually in a heightened state of excitement and it didn't take much for them to do things they hadn't planned, including harming people.
Whanganui Police would like to hear from anyone aware of cigarettes being sold cheaply, or who saw the Subaru stationwagon from Saturday's robbery between August 20 and 26 or knew anything about the distinctive basketball singlet or the robbers. Contact Constable Tim Cameron, on 349 0672.