A man from Florida has been arrested following an FBI investigation that connected him to several extremist group chats on the encrypted messaging app Signal. Authorities assert that he used various aliases to disseminate alarming graphic messages, detailed instructions for making explosives, and violent neo-Nazi propaganda.

Lucas Alexander Temple, aged 20, now faces federal charges related to the distribution of information on manufacturing or using explosives and for possessing an unregistered short-barreled shotgun, as stated in court documents.

Criminal complaints reveal that Temple shared a hand-drawn diagram of a homemade detonator. He also provided links to YouTube videos explaining how to synthesize dynamite and construct blasting caps. Additionally, he posted a 122-page extremist manual replete with White supremacist rhetoric.

Investigators indicated that the chats contained graphic discussions that endorsed rape, torture, and murder, including the killing of non-White children. The case documents detail screenshots of messages allegedly sent by Temple, including disturbing phrases and discussions about sexually assaulting men.

During the investigation, neo-Nazi propaganda was reportedly found in Temple’s home, alongside a driver’s license photo that confirmed his identity.

Screenshots of messages allegedly sent by Temple’s aliases included phrases like, “How long would it take to rape a femboy to death?” and discussions about sexually assaulting men.

Temple’s online aliases were linked to his true identity through personal details shared in chats — including his age, job at a grocery store and a family museum visit — and were verified with state records and security footage, according to the complaint.

While executing a search warrant at Temple’s home on Thursday, FBI agents found neo-Nazi propaganda, a book related to Columbine High School shooters Dylan Klebold and Eric Harris and a Springfield Model 67 Series E shotgun with a barrel shorter than 18 inches.

The barrel was allegedly sawed off and found in a separate area by investigators.

Guns were found inside Temple’s bedroom, according to authorities.

ATF records confirmed Temple was not registered to have the weapon.

Agents also found a handwritten note that said, “Plans: Wear body cams for livestream. Notify friends of livestream. Put flags on car. Play music on car speakers during operation. Place motion-activated bombs in doorways (for cops).”

A handwritten attack plan was found inside Lucas Temple’s bedroom, according to authorities.

During his initial court appearance, Magistrate Judge Amanda Arnold Sansone ordered that he remain detained pending trial, finding he posed a serious danger to others.