The day Russian ambassador Sergey Kislyak mingled with Trump campaign advisers—including then-Sen. Jeff Sessions—at a conference near the Republican National Convention, the Department of Homeland Security began preparing a nationwide warning about foreign intelligence officials attempting to elicit information from U.S. government personnel at conferences, events, and other functions.

The document, eventually released on July 27, 2016, and reviewed by The Daily Beast, doesn’t specifically mention which foreign intelligence service might be making such contacts. But a senior administration official says that growing concern within U.S. government circles about Russian interference in the election generally—and Kislyak’s presence at the RNC in particular—was “not unrelated” to the production of the DHS intelligence bulletin.

Another source confirms the connection, pointing to a section of the bulletin warning of attempts by foreign intelligence officials “to gather intelligence through what appears to be normal, even mundane, social or professional contact” at events including conferences.

This article is based on DHS and other counterintelligence documents and interviews with five current or former law enforcement, intelligence, and government officials with deep knowledge of aspects of the overarching investigation into Russian influence of American politics. Not all of the sources agreed about the importance of the bulletin. Some viewed it as routine and somewhat obvious given its timing just months before an election; others believed it to be a serious indication of the FBI’s long-running investigatory interest in Moscow’s attempts to sway the American political process.

This bulletin, from DHS’s Office of Intelligence and Analysis, was distributed to a dizzying array “federal, state, local, tribal, territorial, and private sector partners to develop priorities relating to existing or emerging foreign intelligence threats to homeland security.”

The bulletin is unusual in several ways. It is rare for DHS’s Office of Intelligence and Analysis to produce such a warning about foreign intelligence; that’s typically the purview of FBI counterintelligence. And while the document is unclassified, it contains a warning prohibiting it from being shared with foreign governments, which “makes zero sense, isn’t enforceable, and is entirely against policy,” said a current government official.

Titled “Counterintelligence Awareness, Foreign Entities: Indicators, Processes and Procedures,” the bulletin details potential counterespionage targets and indicators—taking copious notes and long bathroom breaks, and making software-related inquiries, for example—and warned U.S. personnel to be particularly vigilant during meetings with foreign officials.

“It is important not to draw special attention to you or your coworkers, particularly when meeting foreign officials, to ensure foreign entities do not target your expertise or assume you have placement and access to information of interest,” the bulletin reads. “We recommend preparing simple, unclassified answers should a foreign entity begin to inquire, even if seemingly out of polite curiosity, about you or your work. Lastly, plan deflection tactics to minimize a foreign entity’s ability to ask probing questions or display intrusive behaviors.”

The interactions between the ambassador and Sessions at “Global Partners in Diplomacy,” an RNC-related policy conference co-sponsored by the U.S. State Department and attended by up to 79 other ambassadors, were first reported by The Washington Post. USA Today then reported that conversations between other campaign advisers and the ambassador that took place at that same event. One of those advisers, Carter Page, acknowledged Thursday night on MSNBC that he did speak with Kislyak there.

J.D. Gordon, who spoke on a panel before Sessions and was listed on the conference agenda as a “senior advisor to the Trump campaign,” told The Daily Beast he also spoke with Kislyak at the conference.

“After my panel remarks at the Global Partners in Diplomacy program in conjunction with the GOP National Convention in Cleveland on July 20th, I informally interacted with dozens of ambassadors and senior diplomats after leaving the stage. I chatted with this group as well during an evening reception,” Gordon said. “This includes a brief, informal conversation with Ambassador Kislyak, during which I repeated some of the points made by the campaign on the importance of improving relations with Russia. These were not substantive policy discussions, as the White House has noted. None of these informal conversations lasted for more than five minutes.”

Several other Trump campaign or transition officials who attended the conference also dismissed concern over communications with Kislyak at the conference as idiotic and overblown at best. All said the FBI was wasting its time and resources running down every single person the ambassador approaches.

“Dude is everywhere, so fucking what,” said a member of the Trump campaign of the Russian ambassador. “You don’t think we do the same thing over there?”

“So yeah, we know him and he knows us, and you make small talk and you play that game. If you think that means I can’t handle my shit and we’re all Russian agents, go fuck yourself,” said this Trump campaign staffer, now working with the administration.

“But also seriously, I always wondered if he’s got a twin ’cause that dude is literally everywhere,” the official added, before quickly noting, “Obviously, I know he doesn’t.”

Exactly what Kislyak and the Trump campaign officials discussed at the edges of the RNC last year is not known, but according to the DHS intelligence bulletin, seemingly innocent conversations could assist Russian intelligence operations. Specifically, the bulletin warned of “elicitation: a commonly used and highly effective intelligence-gathering technique using ordinary conversation to extract targeted information from a person in a manner that does not disclose the true intent of the conversation. It can occur anywhere—at social gatherings, at conferences, on ship/facility tours, on the street, over the phone, in writing, or over the Internet.”

A senior former intelligence official said Kislyak does not work directly for Russian intelligence but is “practiced at the art of elicitation and as a student of the U.S. for many years,” takes advantage of overly talkative U.S. officials and others to gather information. That proves useful to multiple branches of the Russian government, the official said, speaking anonymously to describe interactions with Russian intelligence.

A DHS spokesman would not answer repeated questions on the timing of the provenance or timing of the report, saying only, “This document went out via email and the Homeland Security Information Network to stakeholders, as listed in the scope. It’s part of an ongoing effort to inform the department and stakeholders about counterintelligence threats.”

In response to lengthy and detailed inquiry from The Daily Beast, the FBI’s main press office email account responded: “We don’t have any information to provide you on this request.”

The White House did not respond to requests for comment on various aspects of this article.

But it is clear that by the time the DHS bulletin was in production, there were already deep concerns about the Russian role in the upcoming American election.

By July 25, 2016, as the Democratic National Convention kicked off in Philadelphia, FBI officials were already telling reporters that they strongly suspected that the Russian government was behind the hacks of the Democratic National Committee. That same day, Trump tweeted, “The new joke in town is that Russia leaked the disastrous DNC e-mails, which should never have been written (stupid), because Putin likes me.”

On July 27, Trump called for Russia to hack Hillary Clinton’s emails. This DHS foreign intelligence alert was blasted out across the country the same day.

One current law enforcement official, annoyed at repeated questions about this bulletin, scoffed and said the other sources were “reading too much into the tea leaves,” but didn’t dispute that it had been produced on the heels of the Russian ambassador’s conversations at the RNC in July.

According to this official, DHS was aware by July 2016 that there was evidence of Kremlin interference in the election and didn’t want to be accused in any way of not sharing preventative intelligence information beforehand.

The official said the bulletin served multiple purposes but the primary one wasn’t exactly cloak and dagger in nature. “This is also known as one enormous Cover Your Ass,” said the official, explaining that there was a great deal of criticism of how the government shared information immediately after the DNC breach.

“The bulletin is bullshit,” the official said, “but the threat isn’t and people should know.”

—with additional reporting by Tim Mak and Kimberly Dozier