Central Hawke's Bay police constable Andy Walker hasn't had a full night's sleep since his deployment to Christchurch.
But being busy and focusing on the job has helped him through his deployment to Christchurch in the "horrific" aftermath of the March 15 mosque shootings.
Walker is part of the Hawke's Bay Search and Rescue team, most of whom are trained in disaster victim identification (DVI).
"This means when there's an incident with multiple casualties we become involved to help identify the victims," he says.
"It's something we are trained for, you have a job to do and you get on and do it to the best of your ability. But what we were confronted with ... there are images that I won't forget."
Walker says on the evening of March 15 he was given a "warning order" that he might be deployed to Christchurch, as part of the DVI team.
"Deployment orders came through on Saturday night. I was told 'your plane leaves from Napier at 10am, be prepared to deploy for five to seven days'."
After a commercial flight to Wellington, Walker and 17 other police boarded an Air Force Hercules for the flight to Christchurch. On arrival they were taken to Christchurch Hospital.
"There were crowds of people at the hospital doors, family members and more, with a lot of security - armed guards at every entrance. We were taken to meet the head pathologist and walked through the procedure to identify each victim."
The process was meticulous, Walker said.
"We had to have enough evidence to satisfy the coroner as to their identity."
Each victim's family had to fill out a missing persons report - but a lot more in-depth, with details such as the clothing their family member would have been wearing, including colours and sizes, any surgery scars or tattoos, old injuries and dental records.
"The post-mortems had to be held, to prove each victim had died by homicide. Details of clothing, scars, tattoos, dentistry etc would be recorded during the post mortem and these details would be matched to a missing persons report, by a reconciliation team."
Walker started on Sunday as part of the team labelling and cataloguing clothing as it was removed from each victim.
"This was sensitive work. It could only be done by trained personnel. It was also a crime scene.''
While this was happening, the families were becoming desperate to claim the bodies of their loved ones. It is customary for Muslim funerals to be held within 48 hours of a death.
"There were reports that some victims' bodies were being released on Sunday, so other families got quite distraught, wanting their family members back.
"This report was false and caused a lot of distress. We felt for them, but this was a process you couldn't shortcut."
Because of what the police saw and experienced in Christchurch, they have a mandatory trauma referral for mental wellbeing.
Walker says he hasn't had a full night's sleep since the deployment.
"It was confronting. The sheer number of victims ... horrific.
A police officer for 12 years, Walker says in recent years police firearms training has revolved around active shooters.
"The cynics amongst us had thought 'it's not a matter of if - it's a matter of where'. We never would have thought it would be a mosque.
"I have heard from some people who are very upset about the change in the gun laws since the attack. They are law-abiding gun owners and don't want to pay the price for what has happened. They believe it's the person at fault, not the firearm.
"I still believe that myself - it's the person not the gun. But the law needed to change. I can't see a need for MSSA weapons.
"If these guns aren't available, it lessens the chance of them falling into the wrong hands."
Police search warrants executed in December last year in CHB located one M4 rifle, two AK47 rifles and an MSSA.