Supermarket staff are being supported, after a traumatic incident in Dunedin

Four people were stabbed in a random attack at the Cumberland Street Countdown store yesterday.

Three people remain in a critical condition in Dunedin Hospital.

Countdown's Kiri Hannifin has flown to Dunedin, to work alongside staff.

She says getting calls such as this, is her worst nightmare - and she feels deeply responsible for the staff involved.

The store will remain closed today.