Munjala initially told her she couldn't come to his side of the counter.
The woman replid: "F*****g get back or I will kill you. I want cigarettes, I want cigarettes."
He remained calm and backed up with his hands in his pockets while she grabbed cigarettes.
He told her: "Don't take the cigarettes, go back, you will get in trouble."
The woman then made a frightening stabbing gesture with the knife at Munjala.
"I just relied on my training and stayed calm," he said.
The woman left the store with about $1000 of cigarettes and tobacco. Munjala then dialled 111.
"I took a breath and sort of shook a bit. It was a very frightening experience," he said.
It is not the first time the store has been targeted.
"People have come in and asked for cigarettes and then grabbed them and run out," Munjala said.
To those targeting dairies he said: "We are small businesses serving the community. You should not rob us. We are here to provide a service."
If you know the woman, phone police on (03) 363 7400, Crimestoppers on 0800 555 111 or leave information on the Canterbury Police Facebook page.
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