Countdown's key rival supermarket chain, is also seeing growing aggravation within its stores

Foodstuffs NZ stable - includes the Pak'n'Save and New World brands.

It was already looking at a number of technology improvements, before Monday afternoon's attack at the Dunedin Central Countdown.

Four people are recovering in hospital after being stabbed.

A Foodstuffs spokesperson says the Dunedin incident has bought into focus what they need to be doing to keep everyone safe.

They're investigating all options available - including CCTV and facial recognition.