(Bloomberg) -- A QAnon adherent who was under investigation by the FBI sent messages last month saying that “World War 3” would occur on Jan. 6, court records show, the latest indication that federal agents knew about the potential for violence in the days leading to the storming of the U.S. Capitol.

Kevin Strong, an employee of the Federal Aviation Administration in San Bernadino, California, was charged with violent entry and disorderly conduct for his role in the Capitol riot. But according to charging documents unsealed on Friday, the FBI began investigating Strong a week earlier, after an informant told federal agents that he was acting strangely.

The informant said that Strong had “sent messages to another individual claiming that World War 3 is going to occur on January 6, 2021,” the charging documents said. He had also told others to “get ready for Marshal Law,” according to the records, and hung up a flag bearing a QAnon slogan.

In the wake of the riot, the FBI and other U.S. law enforcement agencies have faced intense criticism for failing to act on early warnings that far-right protesters were planning a violent demonstration at the Capitol. FBI agents in Norfolk, Virginia, issued an internal warning the day before the riot that extremists were preparing for violence and “war” at the Capitol, the Washington Post reported last week.

The FBI didn’t immediately respond to a request for comment. But Steven D’Antuono, a senior official in the bureau’s Washington field office, has defended the FBI’s preparation, telling reporters last week that agents had acted on early warnings and even prevented certain suspects from traveling to Washington for the rally.

In the weeks since the riot, the U.S. attorney’s office in Washington has charged more than 100 people with a range of offenses, from assault and trespassing to stealing U.S. property and conspiring to subvert the government. Recently, the investigation has focused on the role of far-right groups like the Proud Boys and the Oath Keepers, as prosecutors explore whether the siege was orchestrated ahead of time. On Tuesday, prosecutors brought the first conspiracy charges, alleging that members of the Oath Keepers planned a coordinated assault on the Capitol.

Strong wasn’t charged with conspiracy. The charging documents said an official in the FAA’s internal investigations department notified the FBI on Jan. 7 that Strong was at the Capitol during the siege. At 6 foot 7 inches (2 meters), Strong cut a recognizable figure in the Capitol, where he was seen on a news broadcast wearing a gray coat and a red hat.

A LinkedIn page in his name says he works in the division of the FAA that maintains air-traffic equipment.

“The FAA reported the situation to the FBI and is supporting the investigation,” the FAA said in a statement on Friday. “We will take the appropriate action based on the information we have.”

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