Updated 8:30 p.m. ET

The man allegedly motivated by an Internet rumor to fire a rifle inside a Washington, D.C., restaurant, was planning a "possibly" violent raid, according to court documents released Tuesday.

Investigators say 28-year-old Edgar Welch spent days prior to the Dec. 4 incident at Comet Ping Pong planning the confrontation.

A federal complaint filed against Welch quotes text messages mentioning "Pizzagate," a baseless rumor claiming the pizzeria housed a child sex ring for Washington elites. Just two days before he entered the restaurant, Welch allegedly texted a friend his plan to raid "a pedo ring" where lives could "possibly" be lost.

"I'm sorry bro, but I'm tired of turning the channel and hoping someone does something and being thankful it's not my family. One day it will be our families. The world is too afraid to act and I'm too stubborn not to," the complaint says, quoting the text.

In another instance, he sent a friend a link to a supposed expose on the restaurant.

In a federal courthouse on Tuesday, Welch was formally charged with interstate transportation of a firearm to commit a crime. Local authorities opted not to charge Welch for the multiple weapons, including the AR-15 he fired, which he transported to D.C. from his North Carolina home.

Authorities have maintained Welch was motivated by the online conspiracy theory plaguing a restaurant known for its family-friendly atmosphere and live music. These new details give a sense of how closely he had followed Pizzagate.

As we've previously reported, Comet Ping Pong entered the realm of conspiracy after emails uploaded to WikiLeaks showed Clinton campaign manager John Podesta referring to the restaurant. Misguided interpretations concluded "pizza" was code for "pedophilia."

Fake-news sites and social networks lent the rumor longevity and reach. Even before Welch's plans to investigate, owner James Alefantis had already been receiving death threats. In an interview a week before the gunman entered his restaurant, Alefantis told NPR:

"They would go into our social media accounts and they would take photographs that were on my Instagram of my friends' children or of my associates' children and post them around thousands and thousands of fake-news sites and on reddit and on YouTube and use these images of happily playing, innocent children as proof of some kind of human trafficking scheme led by the Clintons. ...

"In the case of Comet Ping Pong, we're a beloved neighborhood institution. And so we're very strong in a way. We have great community support. If this kind of attack were leveled at an individual or a less strong small business, it would be — I think could be potentially devastating to some of these people."

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