Mr Horne said while every front-line police officer knew the risks, the shooting brought them home.
"There is a lot of pressure because of the social media age that we live in and one of the first things that crossed my mind was getting to the families of the staff who had been injured and I was on the doorstep of the wife where one of the police officers who was shot within 30 minutes of the occurrence and she already knew."
Mr Horne said three out of the four officers were out of hospital and their recovery was going well.
"Two of them I have spoken to within the last 24 hours and they were both in good spirits.
"They are the two with the least serious injuries.
"For the other two, they are in good spirits, but they have still got a way to go with their recovery."
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He said the focus had rightly been on the four officers who were injured, but all of the team working that day had been through something traumatic.
"It's one thing to know that you're putting yourself at risk, it's quite another when one of your colleagues ends up seriously injured."
Mr Horne said when he got the first call for something like the Kawerau seige he was in two minds.
"There is always two things that are going on in parallel when you get a call like that.
"One part of you is clicking into work mode and thinking about all the practical things that you need to do.
"But then there is another part of you which is very personal because you know these people that are involved.
"Straightaway you are thinking about their welfare, their families, their team, the impact that it's going to have on the wider team."
He said it had a big effect on the Rotorua police team.
"It's interesting some of the comments you get from the community, it's a minority, but some people are almost a little bit blase about it in that they think 'well this is what police officers do'.
"But the fact is every police officer comes to work every day to make a difference and they all know that there are elements of the job that are dangerous, but regardless, getting shot and seriously injured is not normal for anyone and happily for New Zealand it's not normal for police officers either." He said some people hadn't seemed to have grasped that police officers were people.
It was police policy that any staff member involved in a traumatic incident had a debrief. There was access to psychological services, support from police management as well as support from colleagues.
"We work pretty hard at that it's a really important thing, you work hard at making sure they get that support."
He said another effect had been trying to cover the injured officers' shifts.
"People are having to slide in and cover each other and that's something that I have been really impressed with, our team has stepped up and done that. As you would hope no one has complained."
He also wanted to thank the local community for its support.
"I would like to say a big thank you to the community for the support that we have received, we have had some lovely comments on our Facebook, we have had a lot of phone calls, leaders from local iwi have been in touch with us and that has been very encouraging."
The identities of the four officers involved have been suppressed by the courts.
