The gunman prepared for nearly everything. His helmet was cinched tight, his rifle magazines full, and a small cache of firearms were loaded into the car. The only thing he didn’t appear to plan was a route. A GPS squawked to the gunman as he navigated the calm Christchurch streets toward Al Noor Mosque.

In a rampage that lasted a few minutes, the gunman killed 41 worshipers in the New Zealand mosque Friday. Seven others were killed in another mosque three miles away, authorities said, and another victim died at a hospital.

Authorities have released few details about the gunman in the video, who they said is in his late 20s. He was captured and will appear in court on murder charges Saturday morning, authorities said. Two other suspects were also detained.

The live-stream age has collided with the rise of manifesto-wielding mass shooters, and the gunman appeared to carefully coordinate his massacre to roar across the Internet. He appears to have posted Facebook links that broadcast live video from his helmet-mounted camera.

The Washington Post will not distribute the 17-minute video. It shows, in violent and nightmarish detail, the perspective of an alleged killer and highlights the degree of preparation the gunman undertook — with guns and ammunition magazines inscribed with white-supremacist messages.

In the video, the gunman parks in an alley facing Deans Avenue and glances at the passenger seat, where three firearms rest. A semiautomatic rifle covered in white-nationalist slogans is slung on his right shoulder. He activates a strobe light on the weapon, in an apparent attempt to illuminate and disorient his victims.

The shooter grabs a semiautomatic shotgun from the trunk, where two gasoline cans appear rigged with devices. He also wears knee pads.

A group of men chat in the entryway of the mosque as the gunman approaches and raises his shotgun.

“Hello, brother,” a man calls out.

The gunman fires nine rounds in rapid succession at his first victims, tossing his shotgun to the ground when he depletes his ammunition, and quickly levels his rifle at others.

Police said they will provide “a highly visible” presence when New Zealanders return to daily life three days after an attack on two mosques killed 50 people. (Monica Akhtar, Allie Caren, Drea Cornejo, Sarah Parnass, Taylor Turner/The Washington Post)

The rifle-mounted strobe flickers on a group of people shot after they fled toward two corners, where they were trapped.

A man rushes the shooter but is cut down by gunfire.

The shooter doesn’t say anything as he navigates the corridors, shooting at people and picking up magazines he drops. Some are bound together to make reloading faster.

While it is unclear whether more than one gunman fired at the two separate mosques, the gunman in the video does not appear to communicate with others via radio or phone. There are no moments that show tactical coordination with others.

A “14” is shown written on his holographic sight, a possible reference to a slogan linked to Adolf Hitler’s “Mein Kampf.” One inscription references the Schwarze Sonne, or “black sun,” a symbol various far-right hate groups utilize, the Associated Press reported.

The gunman canvasses the mosque before he moves to the sidewalk and fires at bystanders. Then he sprints to the car and grabs another rifle before reentering the mosque. Groans fill the air, and the gunman methodically goes room to room and fires at any person who seems to have potentially survived.

In total, he spends a little less than 200 seconds in the mosque, firing dozens of times before heading outside again to shoot at bystanders. In one gruesome moment, an injured woman crawls and cries for help after she falls into the road.

The gunman hops back into his car, where an apparently curated playlist blares “Fire” by the Crazy World of Arthur Brown.

He drives a short distance before opening fire through the windshield with a pump-action shotgun, shattering the passenger window with one shot. Smoke swirls through the car.

The gunman drives away at high speed. Sirens wail in the distance, and he critiques the massacre that just unfolded, perhaps to himself or anyone watching his broadcast.

“There wasn’t even time to aim, there was so many targets,” he says, after commenting too many magazines spilled out during the massacre.

The video ends as the gunman weaves in and out of traffic. A yellow air freshener sways from the rearview mirror.

In a news conference on Saturday morning in New Zealand, prime minister Jacinda Ardern said the gunman was found to have five firearms during the massacre: Two semiautomatic rifles, two shotguns and a “lever-action firearm.” Ardern said he held a gun license, issued in Nov. 2017.

Prime Minister Jacinda Ardern addressed the terrorist attack in Christchurch, New Zealand on March 16. Here’s a little bit more about her. (Blair Guild/The Washington Post)

YouTube, Twitter and Facebook all struggled to contained the video, which was repurposed and shared across social media even after the companies intervened and began deleting the content.

Various historical references to conflicts involving Muslims are also written on weaponry, including the name Charles Martel.

White supremacists credit Martel “with saving Europe by defeating an invading Muslim force at the Battle of Tours in 734,” according to the Southern Poverty Law Center, which monitors such groups.

Also included was the name Ebba Akerlund, an 11-year-old girl killed in an April 2017 truck-ramming attack in Stockholm by Rakhmat Akilov, an Uzbek man, the Associated Press reported.

Read more: