Prime Minister Chris Hipkins says responders encountered "very difficult circumstances" when they arrived at the scene of the Wellington hostel fire.
At least six people were killed in the fire at Loafers Lodge, which broke out in the early hours of Tuesday. The death toll was expected to rise in what firefighters have described as their worst nightmare.
Speaking to reporters from the scene of the fire, Prime Minister Chris Hipkins said New Zealand had "not seen an event of this scale in quite some time".
"I know they've done everything they could," he said of the first responders. "I want to reiterate my thanks and gratitude to them."
Hipkins added it was a "difficult morning" and described the situation as "quite confronting".
"It's clearly a traumatic situation," he told media.
"We will make sure the victims here are supported, we will make sure the first responders are as well because for our Fire and Emergency crews who were on the scene, clearly this was a traumatic incident for them as well.
"Wellingtonians will feel this. Wellington is a small community... People will be feeling this today and I know people will band together to support each other."
Wellington Central MP Grant Robertson said there are some "extremely traumatised" people at the evacuation centre set up for survivors.
"Many people there have lost absolutely everything they had," Robertson said.
A Fire and Emergency New Zealand spokesperson said the urban search and rescue teams were looking at the safety of the area but he expected fire crews to be inside in the coming hours.
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