A man charged with allegedly making threats against Donald Trump and the Trump family made several references to the QAnon conspiracy theory before his arrest, according to Twitter messages obtained by The Daily Beast.

Pennsylvania State Police arrested Jeffrey Gardner Boyd, 55, on July 31 in Berwick after finding a loaded handgun and ammunition in Boyd’s truck. Boyd is charged with four counts of making terroristic threats to kill Trump, daughter Ivanka Trump, son Donald Trump Jr., and son-in-law Jared Kushner. Boyd, who pleaded not guilty at his arraignment, is being held on $1 million bail. His attorney didn’t respond to requests for comment.

Boyd had initially driven from his home in Tulsa, Oklahoma to Pennsylvania, according to a police report, because he had become convinced that a Pennsylvania woman who posts about QAnon on Twitter was being held hostage by shadowy forces. Boyd allegedly told the woman that he planned to go to Washington, D.C. to shoot Trump or other members of the Trump family, claiming that he was being mind-controlled by the CIA.

The woman, who asked to be identified only by her first name, Kate, told The Daily Beast that she warned the man not to try to ram his truck into a gate at the White House.

“He told me I would never know if he did,” Kate told The Daily Beast.

Boyd’s arrest appears to mark the latest appearance of the QAnon conspiracy theory with a dangerous real-life incident. In June, an armed QAnon believer used a homemade armored truck to block traffic on a bridge near the Hoover Dam.

The growing conspiracy theory, which is based on a series of cryptic clues posted on online forums, portrays a world in which Trump is engaged in battle against the CIA, top Democrats and Hollywood elites, pedophiles, and the “deep state.”

“I’ve been had by the f’ing Deep State and CIA,” Boyd wrote in one Twitter direct message.

In direct messages, Boyd repeatedly referenced QAnon terms. For example, he wrote that he had first encountered the woman on “Calm Before The Storm,” an internet forum devoted to analyzing QAnon clues. In another message, Boyd claimed God was giving him “breadcrumbs,” using the same term QAnon followers use to describe the clues they receive from “Q,” an anonymous poster or group of people who QAnon believers claim is a high-ranking Trump insider.

Boyd also mentioned “Stormwatcher,” a Twitter account that tracks sealed indictments filed in federal court. QAnon believers claim the sealed indictments are proof that Trump will soon arrest high-ranking Democrats like Hillary Clinton.

Once he arrived in Pennsylvania, Boyd went to the woman’s house and discovered that she wasn’t actually being held hostage by the deep state. But Kate worried that Boyd would find out that Trump was coming to Pennsylvania for a rally on August 2.

After initially encountering the man when he arrived at her house by surprise, Kate arranged to meet Boyd the next day for lunch at a nearby barbeque restaurant.

At lunch, according to Kate, Boyd made a number of outlandish accusations, including claiming that Donald Trump Jr. and Kushner were in charge of “MKULTRA,” a now-defunct CIA mind-control experiment. Kate also recalled Boyd saying he was “on a mission.”

Worried that the Trump rally could set Boyd off, Kate pressed Boyd on where he was staying and found out that was he living out of his truck in the parking lot of a Giant supermarket. Pennsylvania State Police, acting on a tip from Kate, arrested Boyd in the parking lot later that day.

“He had already demonstrated he was not in control of his own actions,” Kate told The Daily Beast via email.

Before his arrest, Boyd also made derogatory comments about Trump and members of his family, Kate told The Daily Beast—not typical behavior for QAnon believers, who tend to be staunchly pro-Trump.

But Boyd’s claim that he being turned into a presidential assassin through MKULTRA echoes other clues that make up the QAnon conspiracy theory. In Feburary, “Q” posted a clue hinting that a 2017 incident in which a car went out of control near the Trump motorcade was the result of MKULTRA mind control. In fact, however, the car’s teenaged driver only crashed near the motorcade after her brakes went out.