Two rescued from Adelaide fire

Two people have been rescued by firefighters after they were trapped on a balcony during a unit blaze in Adelaide's north.

Firefighters using a ladder have rescued two people who were trapped on a balcony during a unit fire in Adelaide's north.

Neither was injured in the blaze that started at about 10pm on Saturday in Blair Athol.

The fire damaged at least one unit in the block, with others expected to be damaged by smoke and water.

Police and fire investigators will be examining the cause of the blaze.