Before going on a shooting spree at the Chabad of Poway synagogue in Southern California, the alleged perpetrator posted a letter on the website 8chan. It echoes last month's New Zealand shootings, in which the alleged perpetrator took to 8chan to announce the attacks on mosques in Christchurch.
8chan is the latest website to come under scrutiny in the debate over the Internet's role in radicalizing extremists.
The site, where like-minded users with various interests interact with each other, particularly appeals to people who feel pushed off mainstream social media platforms like Facebook and Twitter. It includes communities that discuss Japanese cartoons and Game of Thrones.
But journalist Robert Evans, who writes for Bellingcat, an online investigative platform, describes some corners of 8chan as "a neo-Nazi gathering place on the Internet where young men try to convince each other to commit acts of terrorism."
Shortly after the deadly Chabad synagogue shooting, a user posted a joke on 8chan's /Pol/ community. /Pol/ stands for politics, but this is an extreme right-wing, racist community. The joke is a before-and-after picture. The before picture is a goofy-looking white guy. The after picture is presumably the same guy dressed in SWAT gear and busting in through a door with a weapon.
Evans says that's precisely the goal of /Pol/ — to radicalize users. Community members offer tips on weapons, discussions about the best translated version of Mein Kampf and pictures of mass shooters portrayed as saints.
"There's a lot of these people trying to prepare for what they believe is the inevitable coming race war," Evans explains about /Pol/. "And also a lot of these people [are] trying to spark a race war by convincing other people to carry out attacks."
NPR reached out to 8chan for comment but got no answer.
It would be easy to dismiss the site as just another chat room for extremists. But Evans says it's no accident that both the alleged Christchurch mosque shooter and the Chabad synagogue shooter where on 8chan.
"You look back in 2006, 2007, when you had neo-Nazis or KKK members gather — 20 people would be a large gathering," Evans says. "The movement was sputtering on empty. And then you get to the point when, in 2017, hundreds were marching in Charlottesville. That is not a coincidence. The Internet is creating these people."
Whether the Internet is creating hate groups or just serving as a gathering place, one thing has become clear: What happens online doesn't stay there.
Brianna Wu is a software engineer who lives in Massachusetts. In 2014, she was targeted in something called Gamergate, in which men threatened female video game players and developers. The harassment started mainly on 8chan.
"They threw bricks through my windows. They sent me hundreds upon hundreds of death threats, rape threats," Wu says. "I've had people from 8chan follow me around just to let me know, 'I'm near you and could hurt you if I wanted to.' "
Wu, who is running for Congress, says the solution is simple. "We need dedicated FBI agents that understand online culture to look at these kinds of extreme crimes and prosecute them," she says.
The FBI says that on Saturday it did get several tips that someone was making threatening posts online. Five minutes after the tips came in, the shooting at the Chabad synagogue began.
It was too late.