Police are warning people against getting involved in violent situations, following Monday's knife attack in a Dunedin supermarket

Four people remain in hospital after being stabbed in the Cumberland St Countdown.

Three are in a serious but stable condition, while the fourth is in a moderate condition.

Police have noted that members of the public stepping in, prevented the attacker causing further harm.

Southern District Police Commander superintendent Paul Basham says they usually tell people that unless they HAVE to intervene - don't.

But he says in this case, people showed a level of bravery and courage that he won't criticise them for.

A 42-year-old man is facing four charges of attempted murder and has been remanded in custody, until his next court appearance in June.