A dairy owner chased away four men who tried to rob his store armed only with a broom and yelling "get ready to die".
The attempted robbery happened in Hikurangi, north of Whangarei, on Sunday afternoon.
Police are still searching for the men, one of whom was armed with a crowbar.
The owner, who did not want his name made public in fear of his and his young family's safety, told RNZ he was not afraid to risk his own life to defend his store.
The men entered his shop while he was cleaning and "banged me on the head and pushed me", he said.
"I just said to them 'get ready to die' because I'm not putting up with this nonsense," he said.
"I jumped on them and chased them away - one ran off and the other three ran to their car."
He said he grabbed a signboard outside his store and threw it at their windscreen, breaking it.
"We have to put ourselves at risk... I'm just defending myself."
He has spent a great deal of money on security as there have been several attempted robberies at his store, including one incident nine years ago when a gun was pointed at him, he said.
"They didn't get away with anything - it's not free, sorry, my friend, I work for it and people should work for it too," he said.
"Previously, people came with a gun and I said 'no, rather you kill me but you're not taking anything from me'."