South Australian shoppers have been told to expect to see police monitoring supermarkets as the state heads into lockdown at midnight.

Police Commissioner Grant Stevens said that officers would be assisting supermarket staff to try ad avoid panic buying.

Mr Stevens said it would be a “particularly challenging time” for supermarket and retail staff and asked shoppers to be patient.

“There is no need for people to rush to supermarkets, and if you do go shopping this afternoon, you should expect you’ll be managed by staff, and police will be on standby to attend,” he said.

“If we do see any civil disorder, we will be taking action. There is no need to be panic buying.

“Supermarkets will remain open.”

All residents across the state, except essential workers, will have to stay home for the next 6 days, from midnight.