White supremacist supermarket killer Payton Gendron published his plans to kill 41 hours before his massacre yet internet giants failed to act, the Mirror can reveal.
Between publishing his murderous manifesto on Google and carrying out Saturday’s attack, which left 10 people dead, he even visited the store he would later target.
On Friday, the teenager entered the Top’s Supermarket in Buffalo, New York, disguised as a homeless person to carry out a “reconnaissance” mission, manager Shonnell Teague confirmed.
Locals have grown increasingly angered by the failings of the big tech companies, with many telling the Mirror they have the "blood of our community" on its hands over their lack of inaction.
They also accused the firms of "doing little if anything" to prevent the spread of hate on their servers that allowed teen Gendron to become indoctrinated in far-right hate.
The growing anger here has put increasing pressure on internet giants who have been accused around the world of doing little to tackle the growing problem.
On Saturday, heavily armed Gendron drove 200 miles from his home in Conklin to Buffalo before live-streaming his attack on black residents.
Using Google, he published his plans online in a twisted 180-page manifesto in which he called for whites to rise up and start a race war at 8.55pm on Thursday.
He also called for London Mayor Sadiq Khan to be killed.
Gendron carried out his on Saturday at 2.30pm.
Following his assault, the 18-year-old's attack was said to have been unstoppable with some officials claiming he had failed to name the Top's Supermarket as his target.
But within his “Great Replacement Theory’ killing manifesto, the teen provided not only the name of the store, its zip code, and the street names he would travel to get there but also a map of the inside of the store.
On page six of his manifesto, Gendron wrote: "Why did you choose (REDACTED) for the place of attack?
"(REDACTED) has the highest black population percentage and isn't that far away. Plus NY has heavy gun laws so it would ease me if I knew that any legally armed civilian was limited to 10 round magazines or cucked firearms.
"I replaced the name of the city to redacted because I'd prefer that the FBI and local police don't know until the attack has started. After the attack can somebody switch it over plz? "
However, 53 pages later, he provides further details pinpointing his exact target.
Anger mounted on the streets outside the supermarket on Monday as several locals demanded to know how his plans for the massacre were not picked up and told to the police or the FBI.
Jerome Davey, 37, said Buffalonians "deserved answers from Google" as to why they allowed such a document to be published.
The father-of-five said: "For 40 hours, this killer's plan was on a server for all to see, yet no one at the media giants picked up on it, let alone the police.
"Companies like Google has the blood of our community on their hands.
"They are doing little if anything to stop the spread of such hate. Profit, not people, is all they seem to care about."
Following the killings, New York Governor Kathy Hochul strongly criticised "social media platforms" for manifesting hate and not immediately taking down Gendron".
She vowed said an investigation would focus on what could have been done to stop him, since he had advertised his views online and had been on authorities' radar.
"I want to know what people knew, and when they knew it,' she said, adding the probe would be "calling upon our law enforcement as well as our social media platforms."
She added: "The social media platforms that profit from their existence need to be responsible for monitoring and having surveillance, knowing that they can be, in a sense, an accomplice to a crime like this. Perhaps not legally, but morally. They've created the platform for this hate to be spewed," she said.
Hochul also said there is "a feeding frenzy on social media platforms, where hate festers more hate."
"That has to stop. These outlets must be more vigilant in monitoring social media content.
"And certainly, the fact that this act of barbarism, this execution of innocent human beings, could be live-streamed on social media platforms and not taken down within a second, says to me there is a responsibility out there," the governor added.
The US Department of Justice is investigating the shooting "as a hate crime and an act of racially-motivated violent extremism," US Attorney General Merrick Garland confirmed.
Despite repeated instances of killers posting their intentions online, including New Zealand mosque killer Brenton Tarrant, little appears to have been done to rid the internet of such hate.
Only last year, a counterterrorism organisation formed by some of the biggest US tech companies, including Facebook, Google and Microsoft, pledged to significantly expand the types of extremist content shared between firms in a database, aiming to crack down on material from white supremacists and far-right militias.
Before, the Global Internet Forum to Counter Terrorism's database focused on videos and images from terrorist groups on a United Nations list. It primarily consisted of content from Islamist extremist organisations such as Islamic State, al Qaeda and the Taliban.
But last year, the group said they would add attacker manifestos - often shared by sympathisers after white supremacist violence - and other publications and links flagged by the U.N. initiative Tech Against Terrorism.
A preliminary investigation found Gendron had repeatedly visited sites espousing white supremacist ideologies and race-based conspiracy theories and extensively researched the 2019 mosque shootings in Christchurch, New Zealand, and Anders Breivik who killed dozens of people at a summer camp in Norway in 2011.
Police were called in to question Gendron after he threatened to shoot a fellow pupil at his high school graduation last year.
So worried were officials at the Susquehanna Valley High School that they brought in cops to investigate.
Police were called in June of 2021 after he made statements that he would shoot fellow students.
"A school official reported that this very troubled young man had made statements indicating that he wanted to do a shooting, either at a graduation ceremony or sometime after," a government source said.
After officers looked into the account, Gendron was referred for mental health evaluation and counselling.
Classmates said he often acted strangely and espoused extremist views on politics.
