On Saturday, President Trump called for an investigation into an unfounded conspiracy theory about MSNBC host Joe Scarborough and the death of a former employee.

Trump’s two Saturday tweets followed earlier posts in May about the baseless theory that Scarborough was involved with the 2001 death of Lori Bolterstein Klausutis, who worked for him when he was a U.S. Representative from Florida.

“When will they open a Cold Case on the Psycho Joe Scarborough matter in Florida. Did he get away with murder? Some people think so. Why did he leave Congress so quietly and quickly? Isn’t it obvious? What’s happening now? A total nut job!” Trump tweeted on May 12.

Klausutis worked in one of Scarborough’s offices in Fort Walton, Fla., as a constituent services coordinator. She died unexpectedly at 28, and an autopsy revealed it was due to an undiagnosed heart condition that caused her to pass out and hit her head, which was the cause of death. Florida police ruled that her death was an accident and there was no foul play involved.

Scarborough had announced he was leaving office one month before Klausutis’ death, which Trump pointed out on Saturday as suspicious.

“A blow to her head? Body found under his desk? Left Congress suddenly? Big topic of discussion in Florida…and he’s a Nut Job (with bad ratings). Keep digging, use forensic geniuses!” Trump tweeted.

Trump further gives credit to the conspiracy theory by calling for “forensic geniuses” and saying he thinks there’s more to the story.

“A lot of interest in this story about Psycho Joe Scarborough. So a young marathon runner just happened to faint in his office, hit her head on his desk & die? I would think there is a lot more to this story than that? An affair? What about the so-called investigator?” he tweeted on Saturday.

CNN host Anderson Cooper called Trump’s claims “utterly heartless” to the Klausutis family. Mika Brezinski, Scarborough’s wife and MSNBC co-host, said Trump was a “sick person” for pushing the conspiracy theory and called for Twitter to take his posts down.