Horror novelist and prolific Hollywood writer-producer Stephen King claimed Thursday that President Donald Trump’s recent Twitter activity offers a “window into an increasingly disordered mind.”

“Donald Trump’s tweets over the last 9 days provide a window into an increasingly disordered mind,” Stephen King tweeted to his over 5 million followers. “Since we are all to some extent his hostages, I find this dismaying and rather frightening.”

Donald Trump's tweets over the last 9 days provide a window into an increasingly disordered mind. Since we are all to some extent his hostages, I find this dismaying and rather frightening. — Stephen King (@StephenKing) November 16, 2018

The Carrie author’s assertion follows a series of tweets in which President Trump criticized special counsel Robert Mueller’s investigation into possible collusion between his presidential campaign and Russia, referring to the probe as a “total mess” and a “total witch hunt like no other in American history.”

“The inner workings of the Mueller investigation are a total mess. They have found no collusion and have gone absolutely nuts. They are screaming and shouting at people, horribly threatening them to come up with the answers they want,” the president tweeted. “They are a disgrace to our Nation and don’t…care how many lives the ruin.”

The inner workings of the Mueller investigation are a total mess. They have found no collusion and have gone absolutely nuts. They are screaming and shouting at people, horribly threatening them to come up with the answers they want. They are a disgrace to our Nation and don’t… — Donald J. Trump (@realDonaldTrump) November 15, 2018

“These are Angry People, including the highly conflicted Bob Mueller, who worked for Obama for 8 years. They won’t even look at all of the bad acts and crimes on the other side,” he continued. “A TOTAL WITCH HUNT LIKE NO OTHER IN AMERICAN HISTORY!”

….care how many lives the ruin. These are Angry People, including the highly conflicted Bob Mueller, who worked for Obama for 8 years. They won’t even look at all of the bad acts and crimes on the other side. A TOTAL WITCH HUNT LIKE NO OTHER IN AMERICAN HISTORY! — Donald J. Trump (@realDonaldTrump) November 15, 2018

King, a frequent critic of the administration, has called for President Trump to be removed from office, calling him “unfit” to serve in a tweet in August 2017.

Donald Trump is unfit for office. Needs to be removed. — Stephen King (@StephenKing) August 11, 2017

The Misery writer once vowed to bar President Trump from viewing his films as retribution for blocking him on the social media platform. “Donald Trump blocked me on Twitter,” King wrote. “I am hereby blocking him from seeing IT or MR. MERCEDES. No clowns for you, Donald. Go float yourself.”