SA petrol station blaze not suspicious

A fire that destroyed part of a petrol station at Riverton in SA's Mid North is not being treated as suspicious.

A fire that has destroyed a petrol station in country South Australia wasn't deliberately lit.

Residents have returned to their homes and businesses have reopened around the Riverton service station, in SA's mid-north, after a 500 metre exclusion zone was declared around the burning building on Tuesday night.

The cause of the blaze, which is not considered suspicious, remains unknown, police say.