"Until he is located, or hands himself in, frontline Level 1 responders in Canterbury will be carrying firearms for their own safety and the safety of the public," he said on Friday.
"Our officers are operating in an environment of heightened risk, and they deserve to be kept safe. Their safety is paramount.
"My intent is simply that my staff can come to work, complete their shifts to keep the public safe, and return home safely to their families at the end of the day."
However, following the arrest of the 20-year-old in Papanui the directive was lifted.