Police have confirmed the death of a 57-year-old man in Paeroa is a homicide.
Jordan Voudouris was found lying in an alley behind his restaurant early on Monday.
Police say a post-mortem examination shows the death was suspicious.
They say they have a team of about 20 staff working on the case.
The police are trying to find out what, if any links there may have been with an attempted robbery of a service station in Waihi and the aggravated robbery of a dairy in Katikati on Monday morning.
Detective Senior Sergeant Mike Whitehead says CCTV footage from the businesses indicates the same offenders, armed with a pistol and hammer, were involved in both robberies.
Leonie Mason owns Granville's Antiques, about five shops from Mr Voudouris' pizza shop, says the manner of the death has made people uneasy.
"Watching their locks, watching who's coming in. We're all unsettled," she said