By NICK PERRY and MARK BAKER Associated Press

CHRISTCHURCH, New Zealand (AP) — At least 49 people were shot to death at two mosques during midday prayers Friday — most if not all of them gunned down by an immigrant-hating white supremacist who apparently used a helmet-mounted camera to broadcast live video of the slaughter on Facebook.

One man was arrested and charged with murder. Brenton Harrison Tarrant appeared in court Saturday morning amid strict security and showed no emotion when the judge read him one murder charge. The judge said "it was reasonable to assume" more such charges would follow.

Two other armed suspects were taken into custody while police tried to determine what role, if any, they played in the cold-blooded attack that stunned New Zealand, a country so peaceful that police officers rarely carry guns.

It was by far the deadliest shooting in modern New Zealand history.

"It is clear that this can now only be described as a terrorist attack," Prime Minister Jacinda Ardern said, noting that many of the victims could be migrants or refugees.

She pronounced it "one of New Zealand's darkest days."

Tarrant, who police say carried out at least one of the shootings, posted a jumbled, 74-page manifesto on social media in which he identified himself by name and said he was a 28-year-old Australian and white supremacist who was out to avenge attacks in Europe perpetrated by Muslims.

The gunman also livestreamed in graphic detail 17 minutes of his rampage at Al Noor Mosque, where, armed with at least two assault rifles and a shotgun, he sprayed worshippers with bullets over and over, killing at least 41 people. Several more people were killed in an attack on a second mosque in the city a short time later.

At least 48 people were wounded, some critically. Police also defused explosive devices in a car.

Police did not say whether the same person was responsible for both shootings. They gave no details about those taken into custody except to say that none had been on any watch list.

Tarrant's relatives in the Australian town of Grafton, in New South Wales, contacted police after learning of the shooting and were helping with the investigation, local authorities said. Tarrant has spent little time in Australia in the past four years and only had minor traffic infractions on his record.

On Saturday, outside one of the two mosques, 32-year-old Ash Mohammed pushed through police barricades in hopes of finding out what happened to his father and two brothers, whose cellphones rang unanswered. An officer stopped him.

"We just want to know if they are dead or alive," Mohammed told the officer.

In the aftermath, the country's threat level was raised from low to high, police warned Muslims against going to a mosque anywhere in New Zealand, and the national airline canceled several flights in and out of Christchurch, a city of nearly 400,000.

World leaders condemned the violence and offered condolences, with President Donald Trump tweeting, "We stand in solidarity with New Zealand." Pakistan's Prime Minister Imran Khan and other Islamic leaders pointed to the bloodbath and other such attacks as evidence of rising hostility toward Muslims since 9/11.

New Zealand, with a population of 5 million, has relatively loose gun laws and an estimated 1.5 million firearms, or roughly one for every three people. But it has one of the lowest gun homicide rates in the world. In 2015, it had just eight gun homicides.

Before Friday's attack, New Zealand's deadliest shooting in modern history took place in 1990 in the small town of Aramoana, where a gunman killed 13 people following a dispute with a neighbor.

On Saturday, the prime minister said the "primary perpetrator" in the shootings was a licensed gun owner and legally acquired the five guns used. Ardern said the country's gun laws will change as a result of the carnage, but she did not specify how.

New Zealand is also generally considered to be welcoming to migrants and refugees. On Saturday, people across the country were reaching out to Muslims in their communities on social media to volunteer acts of kindness — offering rides to the grocery store or volunteering to walk with them if they felt unsafe. In other forums, people discussed Muslim food restrictions as they prepared to drop off meals for those affected.

The prime minister said the attack reflected "extremist views that have absolutely no place in New Zealand."

Immigrants "have chosen to make New Zealand their home, and it is their home," Ardern said. "They are us."

At the White House, Trump called the bloodshed "a terrible thing" but rejected any suggestion the white nationalist movement is a rising threat around the world, saying it is "a small group of people that have very, very serious problems."

Tarrant, in his rambling manifesto, deemed Trump "a symbol of renewed white identity."

At the Al Noor mosque, witness Len Peneha said he saw a man dressed in black and wearing a helmet with some kind of device on top enter the house of worship and then heard dozens of shots, followed by people running out in terror.

Peneha, who lives next door, said the gunman ran out of the mosque, dropped what appeared to be a semi-automatic weapon in his driveway and fled. Peneha then went into the mosque to help the victims.

"I saw dead people everywhere. There were three in the hallway, at the door leading into the mosque, and people inside the mosque," he said. "I don't understand how anyone could do this to these people, to anyone. It's ridiculous."

Facebook, Twitter and Google scrambled to take down the gunman's video, which was widely available on social media for hours after the bloodbath.

In the video, the killer spends more than two minutes inside the mosque spraying terrified worshippers with gunfire. He then walks outside, where he shoots at people on the sidewalk. Children's screams can be heard in the distance as he returns to his car to get another rifle. He walks back into the mosque, where there are at least two dozen people lying on the ground.

After going back outside and shooting a woman there, he gets back in his car, where a song can be heard blasting. The singer bellows, "I am the god of hellfire!" and the gunman drives off before police even arrive.

The second attack took place at the Linwood mosque about 5 kilometers (3 miles) away. Mark Nichols told the New Zealand Herald that he heard about five gunshots and that a worshipper returned fire with a rifle or shotgun.

The footage showed the killer was carrying a shotgun and two fully automatic military assault rifles, with an extra magazine taped to one of the weapons so that he could reload quickly. He also had more assault weapons in the trunk of his car, along with what appeared to be explosives.

His manifesto was a welter of often politically contradictory views, touching on many of the most combustible issues of the day, among them the Second Amendment right to own guns, Muslim immigration, terrorist attacks and the wealthiest 1 percent.

He portrayed himself as a racist and a fascist and raged against non-Westerners, but said China is the nation that most aligns with his political and social values.

The gunman said he was not a member of any organization, acted alone and chose New Zealand to show that even the most remote parts of the world are not free of "mass immigration."

Last year, New Zealand's prime minister announced that the country would boost its annual refugee quota from 1,000 to 1,500 in 2020. Ardern, whose party campaigned on a promise to take in more refugees, called it "the right thing to do."

Christchurch, sometimes called the Garden City, has been rebuilding since an earthquake in 2011 killed 185 people and destroyed many downtown buildings.

Perry reported from Wellington. Associated Press writers Juliet Williams in Christchurch; Kristen Gelineau in Sydney; Rod McGuirk in Canberra, Australia; and Chris Blake in Bangkok contributed to this report.