The owner of a Christian surf school in California who has admitted to killing his two young children because he believed they’d inherited serpent DNA from their mother told the FBI he was radicalized by the former BBC sports presenter-turned-conspiracy theorist David Icke.

Matthew Coleman, 40, told FBI agents last August that in the days before he killed his children, he’d been having visions and seeing signs that revealed to him that his wife, Abby, “possessed serpent DNA” and was potentially a “shape-shifter.”

Coleman said he believed his wife had passed the reptilian DNA on to his children—2-year-old Kaleo and 10-month-old Roxy—and that his children now possessed “corrupted DNA” that would spread if something wasn’t done about it, according to a new court filing reviewed by VICE News.

Ultimately, Coleman drove his two children from their home in Santa Barbara to the Mexican resort town of Rosarito. He told FBI agents that in the early hours of Aug. 9, 2021, he killed both children by stabbing them through the heart with a spearfishing gun. He then dumped their bodies by the side of the road.

Coleman said they were going to “grow into monsters” and killing them was the only way to “save the world.”

Based on his social media posts, Coleman was living an idyllic life on the California coast, as the owner of a successful surf school, a devout Christian, and a loving father and husband.

But court documents have revealed that he and his wife had become radicalized by conspiracy theories and both had begun researching QAnon online. However, Matthew Coleman became more paranoid, seeing signs and symbols everywhere leading him to conclude that everyone from his closest friends and even his wife were part of a conspiracy.