Hours after John McAfee was found dead in a Spanish jail cell Wednesday, a mysterious post popped up on his Instagram page in an apparent reference to QAnon, according to a new report.

A large “Q” appeared without a caption or explanation, the first post on the tech pioneer’s account since he was jailed in October to await extradition to the US on tax fraud charges, Newsweek reported Thursday.

The cryptic post has since been deleted, but has convinced many QAnon conspiracy theorists that it was a reference to their beliefs — and a suggestion he was killed by the “deep state,” according to Vice.

QAnon, a radical right-wing group, preaches that a secret “deep state” of Satanic cannibalistic pedophiles runs Washington, DC.

Q believers floated similar theories after the 2019 death of pedophile Jeffrey Epstein, who committed suicide while awaiting trial on sex-trafficking charges.

McAfee, who was an avid tweeter even after he was jailed in Spain, toyed with QAnon followers on several occasions in the past in bizarre Twitter posts.

“Q is real!!!!” he tweeted on March 12, 2020. “I saw him doing a flagellation scene With Mistres (sic) Kat in San Francisco.”

“Nothing to brag about,” he wrote. “Not masterful or anything — But middle of the road I’d say. Definitely a novice in the S&M scene.”

“The difference between ‘Q’ and McAfee,” he wrote in another post the same day. “No-one knows who Q is. Everyone knows who McAfee is. No-one knows where Q is. @theemrsmcafee Knows where McAfee is.”

“McAfee is an anal fisting Master,” he said. “Q refuser to divulge his own mastery. But I know. Yep… I know…”

After he was jailed in Barcelona in October, McAfee added more intrigue when he tweeted a reference to Epstein after the financier’s suicide.

“Know that if I hang myself, a la Epstein, it will be no fault of mine,” he wrote.

Spanish authorities said the tycoon’s death was an apparent suicide and have ruled out any foul play.