A 36-year-old female civil servant who was stabbed in the neck in Drumcondra is recovering well in hospital.
Gardaí arrested a "volatile" homeless drug addict in the Tallaght area on Wednesday night after officers discovered her "acting very strangely".
Officers feared that the 33-year-old woman may have been planning a crime rampage.
The suspect, who is originally from Co Kildare, has been staying in homeless hostels in Dublin city centre and is known to gardaí for her "violent and erratic behaviour", according to sources.
"There are legitimate fears that this woman may have attacked other people, so it is a relief that she has been taken off the streets.
"Certainly, there were concerns that if she was not picked up, she may well have done serious harm to other people and even gone on a violent rampage."
Gardaí are not looking for anyone else in relation to the stabbing that happened on Drumcondra Road Lower between Clonliffe Road and the Archbishop's House shortly after 5pm on Tuesday.
"The prompt action of gardaí on foot patrol, who assisted the injured woman, greatly assisted in this early arrest," a Garda spokesman said yesterday.
Staff from the Archbishop's House also helped the victim, who they said was staggering and appeared to have lost a lot of blood.
The 36-year-old is understood to be making a good recovery in the Mater Hospital.
However, investigating gardaí have not yet been able to get a formal statement from the victim. Her family did not wish to comment when contacted yesterday.
The attacker demanded that the victim hand over her handbag, before stabbing her in the neck in an unprovoked attack.
She then escaped with the woman's bag, which contained her mobile phone as well as other items.
CCTV has played a major role in the investigation and gardaí obtained footage from the Archbishop's House as part of their probe, as well as from other businesses in the Drumcondra area.
CCTV footage showed the attacker sitting on a wall before the attack, and also the victim lying against a wall after being stabbed by the suspect.
It is understood the suspect was identified shortly after the mugging.
The Archbishop of Dublin, Dr Diarmuid Martin, said it was "very tragic that a person simply waking home from work can be attacked like this and it's not the only attack of this kind in the last few days".