New Zealand’s prime minister has said gun law reforms will be announced within 10 days in the wake of the mosque shootings in Christchurch that killed 50 people.

Jacinda Ardern said Cabinet ministers had met and made an in-principle decision to tighten gun ownership but details still need to be worked out.

Ms Ardern also announced an inquiry into the country’s intelligence services.

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Jacinda Ardern hugs a woman as she visited Kilbirnie Mosque to lay flowers among tributes to Christchurch attack victims on Sunday (TVNZ via AP)

Separately, a Christchurch gun shop acknowledged selling guns online to the alleged gunman.

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

The store “detected nothing extraordinary,” about the buyer, he said.

Meanwhile, Police Commissioner Mike Bush said police are certain a lone gunman was responsible for the shootings.

“I would like to state that we believe absolutely there was only one attacker responsible for this,” he told a news conference.

“That doesn’t mean there weren’t possibly other people in support and that continues to form a very, very important part of our investigation.”

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Gun City owner David Tipple (Vincent Yu/AP)

None of the guns sold were military-style, semi-automatic weapons, according to Mr Tipple.

In vowing to tighten gun laws, Ms Ardern has said the attacker used five guns, two of them semi-automatic, which were purchased with an ordinary gun licence and modified.

Three days after the attack, New Zealand’s deadliest shooting in modern history, relatives were anxiously waiting for word on when they can bury their loved ones.

Islamic tradition calls for bodies to be cleansed and buried as soon as possible after death, usually within 24 hours.

Aya Al-Umari, whose older brother Hussien Al-Umari died at the Al Noor mosque, wept as she talked about a kind man.

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A student lights candle during a vigil to commemorate victims of Friday’s shooting (Vincent Yu/AP

On Monday, the family was still waiting for the release of Hussein’s body.

“It’s very unsettling not knowing what’s going on,” Ms Aya said.

“I understand the police need to do their job because it’s a crime scene, but you need to communicate with the families.”

Members of the Muslim community and police were at a cemetery which has been fenced off and obscured with white netting.

Locates mosque shootings in Christchurch, New Zealand
(PA Graphics)

Kawthar Abulaban, 54, who survived the shooting at the Al Noor Mosque, came to the burial site to see the preparations.

“I will not change my opinion about New Zealand. It’s my country,” said Ms Abulaban who emigrated to New Zealand from Jordan 17 years ago.

“You know I have lots of support, lots of love, lots of kindness from all of the New Zealand people.”

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Students gather for a vigil in Christchurch (Vincent Yu/AP)

Ms Ardern has said authorities hoped to release all the bodies by Wednesday and police said authorities were working with pathologists and coroners to complete the task as soon as they could.

Brenton Harrison Tarrant, an Australian citizen who lived in New Zealand, appeared in court on Saturday where the judge read one murder charge and said more charges would likely follow.