The US Justice Department did not identify the journalists or their news outlets.

A counterterrorism analyst with the US Defense Intelligence Agency was arrested on Wednesday over charges he leaked classified materials about a foreign country's weapons system to two journalists in 2018 and 2019, the US Justice Department said in federal court filings on Wednesday.

Information that 30-year-old Henry Kyle Frese passed to the journalists appeared in at least eight different news stories, the Justice Department alleged in an indictment unsealed in the U.S. District Court for the Eastern District of Virginia.

The two reporters to whom he leaked information were colleagues, and one of them was apparently romantically involved with Frese, the FBI said in court filings.

Those news stories relied on five separate intelligence reports issued between March and June 2018.

The Justice Department did not identify the journalists or their news outlets, but said they each worked for a different outlet owned by the same parent company.

Reuters could not immediately determine if Frese had obtained a lawyer in the case.

This marks the sixth federal case involving leaks of classified information in a little over two years. A crackdown on leaking was initiated by the Trump administration in 2017 and led by then-Attorney General Jeff Sessions.

The first case to emerge during the Trump administration involved Reality Winner, a former intelligence analyst who divulged a report about Russian interference in the 2016 election to the Intercept news website.

Another similar case earlier this year involved a former intelligence analyst named Daniel Everette Hale, who was also charged in connection with leaking information to the Intercept related to a US drone strike program.

Until the criminal case against Winner, no one had been charged with leaking classified information since 2013, said John Demers, the head of the Justice Department's National Security Division, in a call with reporters on Wednesday to announce the charges against Frese.

"Our investigators and prosecutors nationwide will continue to devote themselves to media leak cases in order to protect our nation from the threat posed by the rare intelligence community official who breaks his or her oath," he said.

During the course of its investigation, the FBI learned that Frese was a follower on one of the reporter's public Twitter feeds, and that Frese shared a residential address with the journalist from August 2017 through August 2018.

The reporter with whom he lived is referred to in court records as "Journalist 1."

"It appears that they were involved in a romantic relationship for some or all of that period of time," the FBI agent wrote in a sworn statement.

In the spring of 2018, the FBI alleges Journalist 1 called Frese on his cellphone and the next day Frese started searching for an intelligence report involving topics unrelated to his work responsibilities.

Seven days later, the reporter sent him a direct message on Twitter asking if he would speak with "Journalist 2," who was a more senior and seasoned reporter.

He replied he was "down" to help Journalist 2 because doing so would help Journalist 1 "progress" in her career.

Phone records show he communicated multiple times with both of them, including on the same day an article was published containing classified information from the intelligence reports, the FBI said.