WASHINGTON — A Pentagon counterterrorism analyst shared classified information with two journalists for more than a year, one of whom he was dating, according to an indictment unsealed on Wednesday.
The analyst, Henry Kyle Frese, 30, was arrested on Wednesday at his office at the Defense Intelligence Agency, where he has worked since January 2017, first as a contractor and then as an employee, prosecutors said.
His arrest was the latest in the Justice Department’s aggressive efforts to crack down on illegal leaks of classified information. Six people have been charged with unlawfully sharing government information since Jeff Sessions, then the attorney general, vowed in August 2017 to ramp up the fight on leaks, said John Demers, the head of the department’s National Security Division.
Until 2017, no one had been charged in leak cases since 2013. Law enforcement officials under President Barack Obama prosecuted more leak cases than all previous administrations combined.
“Leaks of classified information cause damage to national security,” Mr. Demers said in a statement announcing the charges against Mr. Frese. Law enforcement officials said that the indictment made clear that the government was not pursuing the journalists in this case.
But federal prosecutors declined to say whether they had monitored the journalists or obtained their records or data. And the methods in the case — a wiretap of Mr. Frese’s phone, perhaps the most intrusive tool in criminal investigators’ arsenal — underscored the Trump administration’s aggression in hunting leaks to journalists.
The Trump administration’s renewed pursuit of leakers has alarmed First Amendment advocates, who say the investigations can have a chilling effect on government employees who may choose to stay silent rather than alert journalists to wrongdoing.
Such indictments are also regularly used by Mr. Trump’s allies to advance rhetoric about a “deep state” of government leakers seeking to undermine his presidency; reporters say their sources are often dedicated public servants concerned about malfeasance or abuse of power.
“This indictment should serve as a clear reminder to all of those similarly entrusted with national defense information that unilaterally disclosing such information for personal gain, or that of others, is not selfless or heroic; it is criminal,” Zachary Terwilliger, the United States attorney for the Eastern District of Virginia, where Mr. Frese was charged, said in a statement.
Mr. Frese will make his initial appearance on Thursday in federal court in Alexandria, Va., where his case is being prosecuted.
The F.B.I. said that it received court permission to wiretap Mr. Frese’s cellphone and intercept some of his text messages and phone calls. The government also received data from Twitter, where he often communicated with one of the reporters.
Mr. Frese shared information classified as top secret with reporters multiple times as far back as April 2018, when he gained access to an intelligence report about an unnamed foreign country’s weapons systems — a topic unrelated to his counterterrorism work, according to court papers.
Mr. Frese shared information from the report with Amanda Macias, a national security reporter at CNBC who was his girlfriend, according to court papers and social media posts. She published eight articles related to information from Mr. Frese and five intelligence reports, according to prosecutors, who identified her only as Journalist 1.
Details in court papers about their communications, their social media accounts and their shared residential address made clear that Ms. Macias was Journalist 1. She did not respond to an email request for comment.
In private messages sent over Twitter in late April 2018, Ms. Macias told Mr. Frese that an American military official knew nothing about the intelligence report he had shared with her. He called the denial “weird” and later searched a classified government computer system for related terms, and called Ms. Frese back.
Within days, Ms. Macias was the first journalist to report that China had installed missiles and missile systems in the South China Sea. When she posted a link to the article on Twitter, Mr. Frese shared her tweet as well.
In private messages, Ms. Macias also asked Mr. Frese to speak with another reporter, Courtney Kube, a veteran Pentagon reporter for NBC News, which like CNBC is part of NBCUniversal. Prosecutors identified Ms. Kube only as Journalist 2. She did not respond to an email seeking comment.
Mr. Frese complied, saying in a message that he would speak to Ms. Kube if it helped Ms. Macias’s career “progress.” Last month, the government said, Mr. Frese gained access to two more intelligence reports and shared them with Ms. Kube.
A spokesman for NBC declined to comment. The suggestion that one of the journalists was involved in a relationship with Mr. Frese may also cause problems for executives at NBC, who would be obligated to examine whether any ethical reporting guidelines were breached.
Michael M. Grynbaum contributed reporting from New York.