The Trump administration is investigating former FBI Director James Comey over a social media post that some government officials and supporters of President Trump are interpreting as a threat to the president.

On Thursday, Comey shared a picture on Instagram of seashells on a beach arranged into the numbers "8647." The caption read: "Cool shell formation on my beach walk."

"Eighty-six" is a slang term that means "get rid of," and Trump is the 47th (and 45th) president of the United States. According to Merriam-Webster , the most common meaning of 86 — which has its roots in the service industry — is to "throw out" or "refuse service to" a customer. The dictionary notes that the term has also come to mean "to kill." But the dictionary says it does not include this meaning in the official entry "due to its relative recency and sparseness of use."

The post sparked uproar among some Republicans, who suggested Comey was threatening the president. Donald Trump Jr. accused him of "calling for my dad to be murdered."

But Comey, who deleted the photo within hours, said he assumed the shells were a "political message," not a violent one. It's unclear who created the shell formation.

Comey has been an outspoken critic of Trump since he led the FBI during the president's first term. Trump fired Comey in 2017, four years into his ten-year term, as he was overseeing an investigation into alleged Russian meddling in the 2016 election.

"I didn't realize some folks associate those numbers with violence," Comey wrote on Instagram . "It never occurred to me but I oppose violence of any kind so I took the post down."

Several Republican politicians are calling for Comey to face consequences ranging from an investigation to an arrest . Homeland Security Secretary Kristi Noem announced late Thursday that her department and the Secret Service are "investigating this threat and will respond appropriately." NPR has reached out to Comey for comment and did not receive a response before publication of this story.

Secret Service spokesperson Anthony Guglielmi told NPR on Friday that the agency is aware of Comey's post and takes "rhetoric like this very seriously."

"The Secret Service vigorously investigates anything that can be taken as a potential threat against our protectees," Guglielmi said.

Some Republicans, including Director of National Intelligence Tulsi Gabbard, say they do not believe Comey was unaware of the term's violent connotations.

"I'm very concerned for the president's life; we've already seen assassination attempts," Gabbard told Fox News on Thursday. "I'm very concerned for his life and James Comey, in my view, should be held accountable and put behind bars for this."

Then-candidate Trump survived two assassination attempts while running for reelection last year.

He was wounded in a shooting during a July campaign rally in Pennsylvania. In September, a man trained his rifle on the president's security detail as he golfed in Florida, but fled after being spotted. The man, Ryan Routh, was charged with attempted assassination of a presidential candidate but has pleaded not guilty — and on Thursday asked a judge to dismiss some of the charges against him.

On Friday, Trump told Fox News that he thinks Comey "knew exactly what he meant."

"A child knows what that meant. If you're the FBI director and you don't know ... that meant 'assassination,'" Trump said in a clip of an interview scheduled to air Friday night. "And it says it loud and clear. He wasn't very competent, but he was competent enough to know what that meant."

'86' has shown up in politics before

This isn't the first time that "86" has caused a stir in U.S. politics.

It seems to have crossed into the political lexicon in 2018, when Sarah Huckabee Sanders — then-press secretary in the first Trump administration — was kicked out of a Virginia restaurant . The restaurant's closing staff wrote "86 Sarah Huckabee Sanders" on their note to the morning manager, a photo of which went viral.

In October 2020, Michigan Gov. Gretchen Whitmer, a Democrat, gave a Zoom interview to Meet the Press with an "8645" pin visible behind her, prompting some Republicans to wonder if she was sending a pointed, or possibly violent, message.

Detroit News reported at the time that Whitmer's team said the Trump campaign's reaction was evidence no one in the campaign had worked in the restaurant industry.

Anne Curzan, a linguist at the University of Michigan, told Michigan Public at the time that the most accurate meaning of the term was likely the same as in the Huckabee Sanders incident.

"It could mean they're fired, that there's no more use for them, they've been asked to leave," she said. "So that meaning is out there as well, which is more relevant to the '8645.'"

The "8647" slogan has quietly become a code for opposition to Trump, circulating in TikTok posts and on protest signs in recent months.

The online publication Distractify reported in March that people use it to mean they don't want Trump to be president.

"The message is vague about how exactly these people want to do that, but it seems that the point is to signal that you don't want Trump to be in the White House," it said.

Republican Sen. Mike Lee of Utah retweeted a photo of one such sign at an anti-Trump protest in April, saying "All Americans should condemn this."

He condemned Comey's post in a 14-tweet thread on Thursday, saying it "hits too close to home — and occurs too soon after two serious, nearly successful assassination attempts … to be dismissed as a joke or harmless hyperbole."

Some liberals see a double standard

Merchandise stamped with "8647," from shirts and hats to bumper stickers and pins, are offered by vendors on sites like Amazon and Etsy. So too, however, are "8646" items — a reference to former President Joe Biden.

NPR has reached out to Amazon and Etsy to ask whether those items violate their seller policies prohibiting items that glorify violence.

Some liberal critics on social media say that Republicans did not seem to take issue when the same slogan — or even more violent rhetoric — was targeted at a Democratic president.

They are pointing to examples of violent rhetoric by the president and his allies, including Trump's 2024 post on Truth Social featuring video of a truck driving on the highway with an image of Biden tied up on the back. In 2021, then-Rep. Paul Gosar, R-Ariz., was censured after sharing an anime video of himself killing Rep. Alexandria Ocasio-Cortez and swinging swords at Biden.

And some have found examples of prominent conservatives using the "86" slogan over the years, digging up far-right influencer Jack Posobiec's 2022 tweet reading: "86 46." In 2024, then-Rep. Matt Gaetz, R-Fla., used the term to describe Republicans who had been removed from office, which did not cause notable controversy at the time.