More than 1,000 students from Christchurch schools and different religions have taken part in a vigil to honour the 50 lives lost after a gunman attacked two mosques in the New Zealand city.

In a park across from the Al Noor mosque, where dozens were killed by a white supremacist gunman, the students sat on the grass in Monday’s fading daylight, lifting flickering candles to the sky as they sang a traditional Maori song.

Hundreds then stood to perform a passionate, defiant haka, the famed ceremonial dance of the indigenous Maori people.

A student lights candle during the vigil
A student lights candle during the vigil (Vincent Yu/AP/PA)

Most of the students spent hours locked down in their schools on Friday as police tried to determine if any other people were involved in the attacks.

Those at the vigil told harrowing tales of being forced to hide under classroom tables or on a school stage behind a curtain, of being instructed not to speak.

After the ceremony officially ended, many lingered, standing in circles, arms draped around each other’s shoulders, singing Leonard Cohen’s Hallelujah and Maori songs.

The students’ vigil was a striking and healing counterpoint to Monday’s developments in the mass shooting.

New Zealand Mosque Shooting
Gun City owner David Tipple (Vincent Yu/AP)

A Christchurch gun shop acknowledged selling guns online to the 28-year-old white supremacist accused of killing 50 people.

At a news conference, Gun City owner David Tipple said the store sold four guns and ammunition to Brenton Harrison Tarrant through a “police-verified online mail order process”. The store “detected nothing extraordinary” about the buyer, he said.

Separately, Prime Minister Jacinda Ardern said gun law reforms would be announced within 10 days and an inquiry conducted into intelligence and security services that failed to detect the risk from the attacker or his plans.

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

There have been concerns intelligence agencies were overly focused on the Muslim community in detecting and preventing security risks.

Police Commissioner Mike Bush said police are certain that Tarrant was the only gunman but are not ruling out that he had support.

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

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

“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.”

None of the guns sold to Tarrant were military-style, semi-automatic weapons, according to Mr Tipple. It was not clear if any of the firearms Tarrant purchased from Gun City were used in the shootings.

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.

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

Tarrant had posted a muddled, 74-page anti-immigrant manifesto online before the attacks at the Al Noor Mosque and Linwood Masjid Mosque, and apparently used a helmet-mounted camera to stream live video of the slaughter.