"Those are the ones under the influence of alcohol and drugs. There's certainly more access to firearms and the Police Association is certainly trying to make the public aware of that," he said.
"It makes it far more difficult when you know the offenders have firearms. They are going to jobs certainly being cautious that a firearm could be present. A 30 per cent increase is quite huge."
Mr Aberhart said he could only remember two or three instances where a gun was involved during his days as a frontline officer but it was now far more common.
"The police department are giving us more access to firearms because they are in the cars of the frontline staff. As the frontline staff get confronted more and more you wonder if it needs to be on the hip, but that's a big step."
The figures provided to the Bay of Plenty Times showed the number of apprehensions for assault with a stabbing or cutting weapon dropped from eight in 2012 to four last year and the number of apprehensions for assault with a firearm increased from zero to one.
The number of apprehensions for assault using another weapon increased from 37 to 45 during the same period.
Western Bay of Plenty area prevention manager Karl Wright-St Clair said firearm-related crime in New Zealand was consistently very low and accounted for only 1.4 per cent of all violent crime although police continued to be vigilant and encouraged firearms owners and dealers to do the same.
"Many apprehensions are the result of us being on the front foot proactively targeting offenders, such as those involved in drugs and organised crime, rather than us reacting to incidents involving firearms," he said.
