Police executed a search warrant at an Oamaru residential address yesterday.
They allege the woman was responsible for the robberies of McAuliffe Jewellers on June 6, and those of Sue Todd Antiques and the Elgin Food Market last Friday.
The three businesses were held up using a pistol or the threat of the firearm, and following the final robbery — that of Elgin Food Market about 4.30pm on June 23 — the pistol was pointed at a member of the public who chased the offender, police have said.
Detective Sergeant Dave Nelson said police were able to identify the offender and execute yesterday’s search warrant due to information from the public.
The quality of footage from the CCTV and other cameras throughout the city had also been of great assistance in the investigation, he said.
He would not say whether a firearm had been discovered during the search yesterday, only that "items of interest have been recovered" by police.
During all three robberies the offender was disguised, leading police initially to search for a solidly built male.
McAuliffe Jewellers was one of two jewellers targeted late last year during early morning raids of the businesses. Det Sgt Nelson ruled out the woman being involved in those incidents.
She remained in police custody last night and will face three charges of aggravated robbery in the Dunedin District Court this morning.