On a gloomy, grey Sunday at Gun City in Christchurch business is booming, with the large, warehouse-style shop humming with more than two dozen customers.

As prime minister Jacinda Ardern considers banning semi-automatic rifles following Friday’s massacre of 50 Muslim worshippers, some gun users are busy stockpiling, fearing their favourite toys will soon be out of reach.

An employee who works at a takeaway shop opposite Gun City, New Zealand’s largest gun retailer, confirmed to the Guardian that business had been “extremely busy” at the rifle store since Friday’s massacre. She said she only usually saw such crowds at the shop’s annual sale.

The employee said despite every other shop going into lockdown during the three-hour event, the doors of Gun City remained open. As police chased the killer and ambulances rushed to attend the injured and dying, streams of buyers entered the doors of Gun City carrying empty rifle bags.

“It was disturbing,” she says.

Gun City has been contacted for comment.

Among the throngs shopping there on Sunday was a former New Zealand soldier who gave his name as Anthony, browsing for bullets. A tall, strong man with a ginger beard and tattoos, Anthony says he uses his riflefor “sport”. He was hoping semi-automatics were not banned, but he and his shooting friends were buying the weapons, which can cost anything from NZ$600 (US$400) upwards.

“I felt anger because I knew it would create a negative tidal wave towards people like me, it creates panic. People see a gun now and they freak out.” says Anthony, who also condemned the attack.

“We have had these guns available for a long time and we very rarely have a situation like this. It’s only because the 1% of people. It’s not fair to blame or to ridicule us, the people who do follow the rules. I don’t think it is fair. I think we are still a safe place.”

At a press conference in Wellington on Sunday, Ardern said she would discuss tightening gun access with her cabinet on Monday, and planned to “verify” information that some New Zealanders were stockpiling weapons.

However Ardern was very clear that New Zealand’s gun laws would change in the wake of the massacre – the same message she has reiterated over and over since hours after the first shots were fired.

Guns for sale at Guns City in Christchurch. Photograph: Eleanor Aigne Roy/The Guardian

“I can tell you one thing right now: our gun laws will change,” said Ardern on Friday. “There have been attempts to change our laws in 2005, 2012 and after an inquiry in 2017. Now is the time for change.”

Rick, another customer at Gun City on Sunday afternoon, said he wanted modified semi-automatic rifles to be banned. There was no reason for anyone to purchase them besides “looking cool”, said Rick, who hunts deer.

“They are far too strong for hunters, they will rip any animal to shreds,” said Rick, who was dressed in a camoflage-style shirt, cap and sunglasses,

Civilians in New Zealand own an estimated 1.2m firearms, according to the 2017 small arms survey. That makes New Zealand’s per capita rate of gun ownership higher than Australia’s, but still far below the US, where there is more than one gun per person.

The country’s gun laws are largely unchanged since 1992, when controls were tightened after the 1990 Aramoana massacre, in which a man killed 13 people with a semi-automatic rifle.

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