"They had a knife and a hammer," he said.
"They were totally disguised and left in a white Honda Odyssey."
The employee was left shaken but able to answer police questions.
"Looking at it, it looks like they took quite a few cigarettes," Mr Restieaux said.
A neighbour, who asked to not to be named, observed the thieves before they entered the store near the intersection of Meeanee Rd and Willowbank Ave. He said the Odyssey occupants appeared to be female and Maori.
"They had hoodies on and I even got my binoculars out and perused them a bit - my eyes aren't great - and they all had hoodies they were pulling up.
"I could see three but it looked like maybe four.
"I thought, they are about to rob someone, but I didn't know they had actually done it. They sat there for a long time.
"I thought perhaps I was being paranoid but I wish I got their [car registration] number."
He said the store had been robbed several times in the 26 years he had lived there but it was usually a smash and grab.
"I went to walk over there one night but they were gone - but that was night-time stuff, this is daytime stuff. Wow.
"To think I was watching them - I am bloody disappointed in myself. What a bugger."
He was concerned about the shop being a robbery target "for quite some time".
"With only one of them there behind the counter, it is an easy target."
Security camera footage from the store was being scrutinised by police.
- Anyone with information is asked to phone the police, which can be done confidentially on Crimestoppers: 0800 555 111.