Mohamed Hassan works through the five stages of grief felt by Muslim New Zealanders after the March 15 attacks. Stage one is denial; he talks to Hassan Raslan, who spent three days helping with the burials.

"This being human is a guest house, every morning a new arrival. A joy, a depression, a meanness, some momentary awareness comes as an unexpected visitor." - Rumi

It is a normal part of trauma to experience dissociation in the face of an overwhelming crisis. A body can shut down, or shut out key pieces of information so that you are able to function. Sometimes that means delaying an emotional response to a tragedy - feelings of pain, loss and sadness are pushed to the back - replaced by a numbness. A denial.

"It felt unreal, you know? Like you were watching a movie or something," saysHassan Raslan, a biomedical engineer from Auckland.

"The more I realised how serious it actually was, it just made me sick to stomach."

This is how many of us felt in the wake of the Christchurch attacks. Dazed. Unable to accept that our tiny Muslim community had been suddenly and violently ripped open, and our places of worship deprived of their safety, we pushed all our feelings aside and got to work.

Within days, a bustling volunteer centre was set up at a local school, and hundreds of Muslims from across the country flew down to lend a hand with food distribution, visiting families and survivors, and most importantly, assist in the mammoth task of washing and burying the 51 victims.

"It hit me really hard on that first day, when there were only three or four people being buried. My friend was there, burying his father, and it was so difficult seeing him in that state. It was just a wrecking ball." Hassan Raslan was one of them.

The first dozen bodies were buried over three days, in a large cordoned section of land at the Memorial Park Cemetery, where 51 empty graves lay side by side. Volunteers wore yellow vests and ushered each body, and its family, to the allocated grave. Then they led hundreds of people from the Muslim community to walk past one by one, pray, pay their respects, and empty a fistful of dirt into the grave.

On the first Friday after, the remaining 40 victims were buried, one after another, across three hours.

"It's not an easy task to bury 40 people. I'm not talking emotionally, I mean physically," he says…

Go to this episode on rnz.co.nz for more details