"That's because we're expecting an influx of gang members in town for the tangi."
He said the police Eagle helicopter would be based in Whanganui and staff had been brought in from the lower North Island.
"We are more than confident we have sufficient resources. If something does happen, we'll be able to respond appropriately."
Police earlier cordoned off Tiki St, around the corner from where Ratana was shot dead last week.
An officer on the scene confirmed it was "probably" related to the shooting.
There were more than 10 police vehicles in attendance and four or five people are in handcuffs being spoken to by officers.
A number of those being detained were wearing the colours of the Black Power gang, known to have a strong presence in Castlecliff.
CIB detectives also attended the scene.
The tangi for Ratana, a Mongrel Mob member, was being held today and an influx of gang members was expected in Whanganui.
Police boosted their numbers in the city and brought in the Eagle helicopter to provide "support and assistance".
Ratana, 27, was shot dead in Puriri St, Castlecliff about 9.40am on Tuesday morning, amid reports of a gang clash in the suburb.
The offenders remain on the run, however it was believed those involved were known to each other and were known to police.
