New Zealand’s cabinet has given its support to gun law changes “in principle” in the wake of the Christchurch mosque shootings, prime minister Jacinda Ardern said.

Further details will be announced by the time cabinet meets again next Monday, she said. Ms Ardern had vowed in the immediate aftermath of Friday’s attacks, in which 50 people were killed, that “our gun laws will change”.

Speaking at a news conference on Monday, she said that cabinet’s backing “ultimately means that within 10 days of this horrific act of terrorism we will have announced reforms which will, I believe, make our community safer”.

Ms Ardern said an inquiry will look into events leading up to the attacks and what might have been done differently.

A Christchurch gun shop owner has admitted selling weapons online to 28-year-old Brenton Tarrant, an Australian citizen who has been charged with murder over the attack.

New Zealand shootings: Victims of Christchurch mosque terror attacks Show all 11 1 /11 New Zealand shootings: Victims of Christchurch mosque terror attacks New Zealand shootings: Victims of Christchurch mosque terror attacks Zakaria Bhuiyan People gather hoping to find out information about Zakaria Bhuiyan who is still missing after the mosques shootings in Christchurch. David Moir/AFP New Zealand shootings: Victims of Christchurch mosque terror attacks Mucad Ibrahim Three-year-old Mucad Ibrahim, the youngest known victim of the mass shooting at two mosques in Christchurch, New Zealand, on 15 March 2019. Abdi Ibrahim via AP New Zealand shootings: Victims of Christchurch mosque terror attacks Nadeem Rasheed Nadeem Rasheed, brother of Pakistani Naeem Rashid who died alongside his son Talha Naeem, 21, who were killed in shooting at a Mosque in Christchurch, at their home town in Abbottabad, EPA New Zealand shootings: Victims of Christchurch mosque terror attacks Omar Nabi Omar Nabi speaks to the media about losing his father Haji Daoud Nabi, 71, in the mosque attack REUTERS New Zealand shootings: Victims of Christchurch mosque terror attacks Ash Mohammed Ash Mohammed, right, talks to a police officer about his father and two brothers who are missing near the Masjid Al Noor mosque AP New Zealand shootings: Victims of Christchurch mosque terror attacks Akhtar Khokhur Akhtar Khokhur, 58, shows a picture of her missing husband Mehaboobbhai Khokhar, 65. AP New Zealand shootings: Victims of Christchurch mosque terror attacks Wasseim Alsati A note is seen on a window of a door at the family home of Wasseim Alsati in Christchurch on 17 March 2019. AFP/Getty Images New Zealand shootings: Victims of Christchurch mosque terror attacks Haroon Mahmood Relatives offer condolences to nephew (centre) of Haroon Mahmood, a Pakistani citizen who was killed in Christchurch mosque shootings. AP New Zealand shootings: Victims of Christchurch mosque terror attacks Farid Ahmed Farid Ahmed (pictured) survived the Al Noor mosque shootings but his wife Husne was killed. AFP/Getty Images New Zealand shootings: Victims of Christchurch mosque terror attacks Syed Areeb Ahmed A relative shows a picture of Syed Areeb Ahmed, a Pakistani citizen who was killed the Christchurch mosque shooting. AP New Zealand shootings: Victims of Christchurch mosque terror attacks Naeem Rashid A relative looks at a picture on a mobile phone of Pakistani nationals Naeem Rashid and his son Talha Naeem (right) who died in the Christchurch shootings. AFP/Getty Images

At a news conference, Gun City owner David Tipple said the store sold four guns and ammunition to Mr Tarrant through a “police-verified online mail-order process”.

The shop detected “nothing extraordinary” about the buyer, he said. None of the guns sold to Mr Tarrant were military-style, semi-automatic weapons, the store owner added.

Calling for gun laws to be tightened, Ms Ardern has said the mosque attacker used five guns, two of them semi-automatic, which were purchased with an ordinary gun licence and modified.

It was not clear if any of the firearms Mr Tarrant purchased from Gun City were used in Friday’s shootings.

“My staff and I are dismayed and disgusted by what happened last Friday afternoon,” Mr Tipple said. “We cannot comprehend how such despicable actions could be carried out on those at prayer in a place of worship.”

Mr Tipple said he felt no responsibility for the tragedy and refused to say whether he believed gun ownership laws should change in New Zealand, insisting a debate over guns should be held at another time.

“This man wrote in his manifesto that the purpose of using a firearm was to divide us,” Mr Tipple said. “If we allow him to make changes in our ideology, in our behaviour, he’s won.”

His store has been criticised, in the wake of the shootings, for leaving out a roadside advertising billboard that shows a parent helping children with rifle target practice.

Mr Tarrant, an Australian citizen who lived in New Zealand, appeared in court on Saturday amid strict security.