Q: In this task, you are given an article. Your task is to summarize the article in a sentence.
Jeff Sessions said the suspects were accused of divulging classified material or concealed contacts with foreign intelligence officers.
America's top prosecutor said the administration has tripled the number of active leak probes since January.
President Donald Trump has criticised Mr Sessions as "very weak" on leaks.
At Friday's news conference, the attorney general said no government could be effective when its leaders could not talk freely in confidence with foreign leaders.
"I strongly agree with the president and condemn in the strongest terms the staggering number of leaks undermining the ability of our government to protect this country," he told reporters.
He said there had been a "dramatic" increase in recent months of unauthorised disclosures to the media and even foreign adversaries.
The attorney general also said he wanted to review policies on media subpoenas - compelling journalists to reveal sources - to balance the role of the press with protecting national security.
The move is likely to send a chill through US newsrooms that have been breaking almost daily scoops, which have embarrassed the White House.
Jeff Sessions spoke about the Justice Department's efforts to crack down on national security leaks before television cameras and reporters, but his intended audience was almost certainly the man in the Oval Office.
Last week the president lambasted his attorney general for not doing enough to stifle a torrent of leaks over the past six months. On Friday morning Mr Sessions essentially replied: "See? I am doing something!"
What's more, the attorney general served his anti-leak entree with a generous helping of media-bashing, warning that while he respected freedom of the press, he was reviewing when prosecutors could force journalists to reveal their sources - or face criminal sanction.
That's a dish specially crafted for the president's tastes.
Earlier this week, newly minted chief of staff John Kelly reportedly called Mr Sessions and told him that, despite the president's recent swipes, his job was safe. Perhaps Friday's event is part of a larger effort at fence-mending between the commander-in-chief and his former political confidant.
The attorney general will have to deliver results, however. If he can't stop the leaks, it is doubtful the president will be satisfied. And if there's one truth in Washington, it's that the leaks never really stop.
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A:
The US attorney general has said four people have been charged over leaks as the Trump administration launched a crackdown on embarrassing disclosures.