More than a million litres of wine was drained from tanks at a Riverland winery earlier this week, sparking a plea for help from the public.

Police believe the property damage occurred at the Monash winery in South Australia some time between 3:00pm on December 28 and 9:00am the following morning.

About 1.2 million litres of wine was drained from four separate tanks.

Anyone with information about the incident is urged to contact Crime Stoppers.