SA exclusion zone lifted, three charged

An exclusion zone around a disused petrol station on South Australia's Yorke Peninsula has been lifted.

Police were called to the Marno Street property at 2am on Thursday following reports of suspicious activity.

Homes and businesses within a 300-metre radius were evacuated and people were only able to return about 7pm.

Three local men have been arrested and police allege they poured an unknown substance into two underground petrol tanks, each containing about 200 litres of fuel.

The trio - two aged 27 and one aged 31 - have been bailed to appear in the Maitland Court on November 10.