People in the New Zealand city of Christchurch honoured the 51 worshipers who were killed in a mass shooting a year ago in small but poignant ways on Sunday, after a planned national memorial event was cancelled due to fears it might spread the new coronavirus.

Outside the Al Noor mosque, dozens of leather-clad bikers from the Tu Tangata club performed a traditional Maori haka. They were welcomed by mosque imam Gamal Fouda, who said people of all beliefs and cultures were stopping to pay their respects, and they were all united as New Zealanders.

One of those who survived the shooting at the Linwood mosque was Mazharuddin Syed Ahmed, who said that marking anniversaries was not typically a Muslim tradition but they were doing it so the wider community could grieve and remember. He said the shootings had provoked an outpouring of love and compassion.

"Of course, we lost our loved friends, family, people and community," he said. "But we are also seeing so much good has come out of it. So looking at the positive part of that. Today, it is such a privilege to be in this country."

Temel Atacocugu, who survived after being shot nine times at the Al Noor mosque, said the anniversary had provoked strong feelings.

"We are sad more than we are angry," he said. "It's very emotional. When I woke up this morning, I'm speechless. I can't explain what I feel."

Prime Minister Jacinda Ardern on Saturday said the decision to cancel the memorial event planned for Horncastle Arena was pragmatic and precautionary.

New Zealand has had eight confirmed cases of COVID-19.

All of those cases have been connected to people returning from abroad and so far there haven't been signs of a local outbreak.

Ardern has enacted strict border rules in an attempt to prevent the disease from taking hold in New Zealand.