The woman at the centre of the 12-hour siege in Lower Hutt overnight will appear in court tomorrow after allegedly taking a relative hostage.
The 25-year-old is to appear in the Hutt Valley District Court on charges of kidnapping, threatening to kill, and possessing an offensive weapon, Area Commander Inspector Sean Hansen said.
The weapon charge did not relate to a gun - Hansen confirmed there was no gun involved.
The woman was taken into custody this morning after a dramatic end to an overnight siege at a block of flats on Kings Crescent.
An explosion went off about 8.30am as Armed Offenders Squad officers stormed the building.
Police confirmed officers had used a flash bang to disorientate the alleged offender, allowing them to enter the building safely.
Afterwards, a woman was seen being carried to a waiting ambulance with what appeared to be an AOS helmet on her head.
Hansen said the alleged victim was a 47-year-old woman and was related to the other woman, but would not say what the relation was.
Both women sustained minor injuries when police entered the flat.
"Both were assessed and treated at Hutt Valley Hospital."
Salvation Army's Major Lee Edney said both women were living at the flat, and had been doing so for about a month.
The flats are used in the Salvation Army's "transitional housing programme", providing temporary accommodation with wrap-around support services to people who need help getting into long-term housing.
Edney said no other tenants had been displaced due to damage at the flat.
"This was a family who was in a very tricky situation and very stressed. It is a one-off incident and we will be open to working with the family once matters have calmed down and they know where they're at."
Hansen stressed there was never any danger to neighbours or other members of the public.
"During the course of the incident there were a number of officers from our front line, public safety team staff, from police negotiating team, Armed Offenders Squad, all doing their job ... doing their job really, really well."
The property was cordoned off last night and the incident had been drawn out overnight.
"Ultimately, the fact that we were able to make the effective entry, arrest, and apprehend the offender, largely with no real harm or no real injury to anybody, is a really pleasing outcome."
Hansen said it was too early to say what the motivation behind the alleged kidnapping was, but he expected that to come to light over the next couple of days.
"I acknowledge the patience of the neighbours and a lot of the community who were affected."
The flats, owned by the Salvation Army, have been left with windows blown out and dangling from hinges, and a large hole can be seen in a wall inside.