Witnesses described seeing bodies and “blood everywhere” following the attack at the Masjid Al Noor mosque in central Christchurch at about 1.45pm.
Police have arrested an Australian citizen – a 28-year-old man – and another three people, following a second shooting at another mosque in the Christchurch suburbs.
Brenton Tarrant, named as the suspect in Australian media, appeared to have live-streamed the attack in Christchurch and outlined his anti-immigrant motives in a manifesto posted online.
A search of a property in Dunedin, around 200 miles to the south, was carried out by police.
Videos and documents posted online appear to suggest that the shooter live-streamed his attack on Facebook and prepared an anti-immigrant “manifesto” prior to the shooting.
Prime minister Jacinda Ardern has raised New Zealand's national security threat level from low to high.
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