CNN’s Anderson Cooper warned that longtime Trump associate Roger Stone is skating on thin ice after narrowly avoiding prison for Instagramming a photo showing crosshairs near the head of a federal judge.

“It’s all fun and games until someone threatens a federal judge and almost gets sent to jail for it,” Cooper said during his Thursday night monologue.

″Today, a judge signaled as clearly as she could without actually imprisoning him that yes, playtime is over,” Cooper continued. “No more Nixonian gestures on the courthouse steps the way it was at his first court appearance ... No more talking about being the victim of a deep state conspiracy, as he’s been doing lately, and which the judge today took exception to.”

Earlier in the day, Judge Amy Berman slapped Stone with a gag order, preventing him from speaking publicly about his case. Stone, a longtime ally of Donald Trump and self-proclaimed dirty trickster political operative, is charged in a seven-count indictment with lying to Congress, obstructing justice and witness tampering in special counsel Robert Mueller’s probe of Russian interference in the 2016 election.

“Whatever you think of all of this, things are getting very serious very quickly,” Cooper added, pointing to the walls closing in on other Trump associates, Paul Manafort and Michael Cohen, and the potential end of Mueller’s investigation.