Christchurch residents may need help to recover from the traumatic shootings at two Christchurch mosques on Friday, a mental health expert says.
The Canterbury District Health Board said it plans to begin to offer support soon.
However, others working in the field say many psychological support workers in the city are already exhausted and there are fears that progress made in people's mental health after the Canterbury earthquakes may be at risk.
Mental Health Board chief executive Shaun Robinson told Morning Report today that like many others he is gutted about what has happened. Cantabrians will be experiencing a range of emotions, and should not feel guilty, he said.
"It's all right to feel bad, it's all right to feel whatever you feel. It's really natural to have strong emotional reactions or no reaction at all, to feel numbness or distance," Mr Robinson.
Some people will be relieved they weren't involved, and that may make them feel guilty.
"Others are going to feel deep association with the people involved and feel traumatised and sad and I know some of those people I've talked to this morning."
People should check in with friends and neighbours and support each other but they will recover.
"Absolutely, people will be able to survive and recover from this, individuals, communities and whānau are resilient but yes people may need help."
But a Christchurch-based expert on youth health and post-disaster counselling, Sue Bagshaw, said the shootings come on top of earthquake trauma and there had been no let-up for the city.
Initial psychological first aid after the earthquakes was followed up with treatment for post-traumatic stress disorder. The difficulties with the city's recovery in terms of insurance companies and other uncertainties had made it "worse for everybody".
"It's amazing the response we've had, but at the same time I do think counsellors are tired.
"In fact, one of my colleagues has suggested starting a fund so that counsellors can go away on holiday after this and just regroup. Some of them haven't had a holiday."
Another worry was the atmosphere of stress and anxiety had made Christchurch a difficult place to grow up.
"We've got a whole generation of children and young people who've grown up in that kind of atmosphere and it's not a healthy atmosphere to grow up in."
Dr Bagshaw urged those living in other parts of New Zealand to visit Christchurch so they could get a better understanding of what residents had undergone in the last few years.
GP Phil Schroeder of the Canterbury Primary Response Group said the shootings may unravel progress in mental health post-quakes.
"It makes us feel very vulnerable. It makes us feel that if we felt in control of our situation certainly we aren't always."
Canterbury District Health Board chief executive David Meates said it could be weeks or months before some of the pressures emerge from the community because of the way people react to trauma.
"We do have a community that has dealt with uncertainty over many many years."
He said the health board would look to build up the underlying resilience of the community and that work would start immediately.