It happened in west Dublin
The incident happened in Blanchardstown just before midday.
The woman, in her 60s, was assaulted in her own home in the Willow Wood area.
A man, who was known to the victim, has been arrested and is being questioned at Blanchardstown Garda Station.
A number of Gardai, including members of the Armed Support Unit, were involved in making the arrest and investigations are ongoing.
