New Zealand has been placed on its highest security threat level after a gunman killed 49 people and wounded more than 20 at two mosques in Christchurch.
In an act condemned as terrorism by Prime Minister Jacinda Ardern, an attacker broadcast online live footage of the assault after publishing a so-called manifesto in which he denounced immigrants.
It is the country's worst ever mass shooting.
Ardern said four people who held extremist views were in police custody, three men and one woman, but had not been on police watchlists.
“We believe that 40 people have lost their lives in this act of extreme violence,” Ardern said. “It is clear that this can now only be described as a terrorist attack.”
“This is one of New Zealand’s darkest days,” she added.
What has happened in Christchurch is an extraordinary act of unprecedented violence. It has no place in New Zealand. Many of those affected will be members of our migrant communities – New Zealand is their home – they are us.— Jacinda Ardern (@jacindaardern) March 15, 2019
The apparent gunman’s footage was circulated on social media, seeming to show him driving to one mosque, entering it and shooting randomly at people inside.
One man who said he had been at the city’s main mosque, Al Noor, told media the gunman was white, blond and wearing a helmet and bulletproof vest. He entered the mosque as worshippers were kneeling for prayers.
“He had a big gun ... he came and started shooting everyone in the mosque, everywhere,” said the man, Ahmad Al-Mahmoud. He said he and others escaped by breaking through a glass door.
Australian Prime Minister Scott Morrison said one of the men in police custody was an Australian.
All mosques in New Zealand had been asked to shut their doors, police said.