Armed police have stormed a house in Lower Hutt on Thursday morning to end a hostage situation.
The armed offenders squad used stun grenades at the Kings Cres property to bring the siege to an end.
Witnesses heard loud bangs before police charged.
A 25-year-old woman has been taken into custody, and another woman is being treated by ambulance staff.
Lower Hutt mayor Ray Wallace told Newshub he had been in contact with police.
"Those stun grenades were used to gain entry to disorientate the person inside and that was successfully executed," he says.
"The hostage is fine and obviously the perpetrator is now in custody."
Multiple police cars are at the location. They've been at the scene since around 8pm Wednesday night, along with firefighters and ambulance staff.
"This was a hostage situation overnight," Mr Wallace says.
"Both people know each other and it was a relationship that got out of control."
A number of homes have been cordoned off. Metlink says bus services on Kings Cres have been diverted down High St until the cordon is lifted.
A police spokesperson says there was no risk to the public.