The shooter behind the New Zealand mosque attacks sent his manifesto outlining his sick philosophy to government officials and media outlets less than 10 minutes before the attack that killed 49 people, according to a report.

The New Zealand Herald said the 16,500-word screed was sent to the New Zealand Prime Minister, the country’s National Leader, as well as domestic and international media. However, it did not mention his plans for the mass shooting.

The revelation is the latest news that showed how large a role technology played in shooter Brenton Tarrant’s planning of his crime, which was live streamed via Facebook. He also posted on the 8-chan message board.

Tarrant outlined his reasoning for the terrorist attacks in the 74-page document sent to officials and media.

“The mail was setting his reasons for doing it. He didn’t say, ‘This is what I am about to do.’ There was no opportunity to stop it,” a New Zealand government spokesperson said. Instead, the manifesto said actions were “revenge” for worldwide Islamic terror attacks.

YouTube, Twitter and Facebook removed horrific video footage recorded during the terrorist attacks.  Tarrant also used a message board on 8chan to announce his plan to stream the killings live on Facebook.

The 17-minute footage he shot with a helmet camera was viewed by more than 200,000 people, according to multiple press reports. It was also mirrored and circulated across the internet for hours afterward and is still viewable. The shooter also included references in a 74-page manifesto to Fortnite, conservative pundit Candace Owens and YouTube personality PewDiePie, who has the most subscribers of any on the site.

Those references appeared to be designed to capitalize on the way search algorithms tend to surface information.

Soon after the news of the attack surfaced, Facebook tweeted a statement about the situation attributed to New Zealand-based staffer Mia Garlick. “Our hearts go out to the victims, their families and the community affected by the horrendous shootings in New Zealand,” the statement said. “Police alerted us to a video on Facebook shortly after the livestream commenced and we quickly removed both the shooter’s Facebook and Instagram accounts and the video. We’re also removing any praise or support for the crime and the shooter or shooters as soon as we’re aware. We will continue working directly with New Zealand Police as their response and investigation continues.”

YouTube also tweeted a statement soon after the news broke. “Our hearts are broken over today’s terrible tragedy in New Zealand,” it said. “Please know we are working vigilantly to remove any violent footage.”

Twitter has also been battling to remove shared videos. “We are deeply saddened by the shootings in Christchurch on Friday,” a company spokesperson said in a statement. “Twitter has rigorous processes and a dedicated team in place for managing exigent and emergency situations such as this. We also cooperate with law enforcement to facilitate their investigations as required.”

The vulnerability of the platforms to exploitation by extremists or even more garden-variety criminals has been a topic for years, and several violent incidents have repeatedly put the issue back into the spotlight. Tech companies have pledged to improve their filtering and prevention efforts while balancing those measures against the drive to protect the open spirit of the platforms, which enabled them to grow so explosively over the past decade.