Woman suspected of Adelaide arson attack

A woman suspected of setting fire to an outside awning of a house occupied by a person known to her is being questioned by Adelaide police.

Police arrested her at 6.30am on Thursday, after a driver alerted emergency services two hours earlier after noticing the small fire at the front of the St Marys home.

No one was at home and the fire was extinguished before it could spread to the house.

Police say the suspect is expected to be charged with arson.

They believe the woman and the occupant of the house are known to each other.