South Australians will hunker down at home from midnight tonight, amid a new COVID-19 outbreak in the state.

SA Premier Steven Marshall says the lockdown will act as a "circuit breaker", while a contact tracing blitz is conducted. "We are going hard and we are going early", the premier says. "Time is of the essence".

South Australians will go into six days of 'extreme lockdown' to begin with, followed by eight days of softened restrictions.

For the next six days, all schools, universities, restaurants, pubs, cafes and even takeaway food outlets will grind to a halt, along with the construction industry, according to ABC News. Exercising outside of the home will be banned.

Only one member of each household will be permitted to leave home per day, and only to shop for groceries. SA residents are being encouraged to wear a mask while doing so.

Supermarkets will remain open, as will medical services (including mental health support). Public transport will also continue to operate.

Chief Public Health Officer Professor Nicola Spurrier says the extreme measures are being put in place because of a particularly aggressive strain of COVID-19 which is breeding "very, very rapidly", and to prevent the need for a longer, Melbourne-style lockdown down the line. "If we leave this any longer… then we will be in this for a long haul", she said.

More information about the 'circuit breaker' has been posted by the SA Police. You can contact the SA COVID-19 Information Line on 1800 253 787 between the hours of 9am to 5pm, or jump over to the SA Health website.

Stay safe, SA!

Written by Reena Gupta, a Melbourne-based writer at MTV Australia. Follow her on Twitter @purpletank