New York Attorney General Letitia James announced Wednesday her office will investigate Twitch and Discord, among several other social media companies and platforms, for their connections to the mass shooting that took place in Buffalo on Saturday.

Reporting has revealed Payton Gendron, the 18-year-old responsible for the massacre, posted on several different platforms about his racist beliefs and plans for the shooting months in advance of the attack. He also streamed the attack live on Twitch, though the live-streaming site says the stream was taken down within two minutes of the first instance of violence.

"The terror attack in Buffalo has once again revealed the depths and danger of the online forums that spread and promote hate," James said in a statement. "The fact that an individual can post detailed plans to commit such an act of hate without consequence, and then stream it for the world to see is bone-chilling and unfathomable. As we continue to mourn and honor the lives that were stolen, we are taking serious action to investigate these companies for their roles in this attack."

The Attorney General's office also names 4chan and 8chan as targets in the investigation.

"Time and time again, we have seen the real-world devastation that is borne of these dangerous and hateful platforms, and we are doing everything in our power to shine a spotlight on this alarming behavior and take action to ensure it never happens again," James concluded.

In a statement, Twitch said it takes protecting its community "extremely seriously."

"As we've shared in the past, live content moderation presents unique challenges, and we are continuously evaluating our policies, processes, and products to keep our community safe," Twitch said in this week's statement. "We'll be examining this incident carefully and sharing those learnings with our peers in the industry to support a safer internet overall."

Discord told CNN it had removed Gendron's server "as soon as" it was aware of it after the shooting.

"Our deepest sympathies are with the victims and their families," said a spokesperson. "Hate has no place on Discord and we are committed to combatting violence and extremism."