Thanks to a police training course the same day as the Christchurch terrorist attack, specialist staff from overseas, as well as New Zealand's Defence Force, were on hand to help.
Personnel taking part in the course in the city centre were already wearing their gear when the first 111 call was received at 1.41pm on Friday, March 15.
Fifty people were killed and dozens more injured in the massacre, which had been timed to coincide with Jumu'ah, a congregational prayer that has Muslims shoulder-to-shoulder in mosques not long after noon each Friday. Fortunately, it also happened to coincide with a gathering of some of the world's best sharpshooters.
Individuals from the police special tactics group (STG), NZDF, Australian and Hong Kong police, were involved in the response, a New Zealand Police spokesperson said.
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They had "advanced specialist medical first aid training" and were sent to the two scenes — the first, Masjid Al Noor on Dean's Avenue, and the second, Linwood Masjid — to provide immediate medical assistance.
They carried firearms, given it was thought armed offenders were at large at that time, and provided first aid to a number of victims "in the most difficult of circumstances".
New Zealand Special Air Service (NZSAS) soldiers were photographed at the scene wearing plain clothing and balaclavas, armed with sniper rifles.
One of the SAS's main roles is combating terrorism. That role is activated by the Prime Minister, at the request of the Police Commissioner.
GETTY IMAGES
Police officers carrying automatic rifles guard the area near Al Noor mosque during a visit by Turkey's Vice-President Fuat Oktay and Foreign Minister Mevlut Cavusoglu on March 18, 2019 in Christchurch.
NZDF referred requests for comment to NZ Police, who said the commissioner didn't ask for assistance on Friday. But soldiers who were attending the training helped, under police direction.
"We are very grateful for the support these defence personnel provided to both police and the public in a horrific situation," the spokesperson said. "Their actions are a testament to the professionalism, skills, and the inter-agency operability of specialist groups in police and defence."
Police Association president Chris Cahill said he couldn't comment on international forces, but said police across the Asia-Pacific region generally have a close relationship.
The timing of the training course would have helped with a rapid response, he said. "You need a bit of luck sometimes."
The first armed officers arrived at Al Noor mosque six minutes after the callout. The armed offenders squad (AOS) arrived within 10 minutes. Cahill described the response as "outstanding".
The gunman was arrested 36 minutes after the call, by two officers, both from small towns outside Christchurch, who rammed the alleged shooter's Subaru Outback and dragged him from the car.
Prime Minister Jacinda Ardern praised the officers' actions, saying it was "absolutely" the gunman's intention to continue with his attack.
Police Commissioner Mike Bush said he'd received an "absolutely overwhelming positive response" from the public. "It's been heart-warming, the commentary we're getting about our people. We couldn't be more proud of our people."