In this May 14, 2013, file photo, the Department of Justice headquarters building in Washington is photographed early in the morning. The Department is planning to disclose a series of Iran-related investigations, raising concerns among some officials. (J. David Ake/AP)

Justice Department officials are preparing to announce several cases involving Iranian suspects in the coming month, including charges stemming from the high-profile hacking of HBO, according to people familiar with the matter.

Last month, national security prosecutors at the Justice Department were told to look at any ongoing investigations involving Iran or Iranian nationals with an eye toward making them public.

The push to announce Iran-related cases has caused internal alarm, these people said, with some law enforcement officials fearing that senior Justice Department officials want to reveal the cases because the Trump administration would like Congress to impose new sanctions on Iran. A series of criminal cases could increase pressure on lawmakers to act, these people said.

Some federal law enforcement officials have also voiced concerns that announcing the cases, rather than keeping them under seal, could imperil ongoing investigative work or make it harder to catch suspects who might travel out of Iran, according to the people familiar with the matter who spoke on the condition of anonymity to discuss ongoing investigations.

A Justice Department spokesman declined to comment.

One case involves the hacking of HBO. The cable channel has faced several embarrassing computer intrusions, the most serious being in July and August when the company announced hackers had stolen data. In that instance, hackers claimed to have stolen 1.5 terabytes of data, according to people familiar with the breach.

The hack reportedly exposed scripts from the popular show “Game of Thrones’’ and an executive’s emails. The hackers said in communications with news organizations that their motive was simple: get money from the company in exchange for not publicizing additional information.

It’s unclear if HBO ever paid the hackers money, but the same online hacker persona also leaked what appeared to be an offer from the company to pay them money as a “bug bounty’’ — indicating the hackers had grown frustrated they hadn’t received any payments yet.

An HBO spokesman did not respond to messages seeking comment.

The HBO hack was jarring to the entertainment industry because it seemed to be a repeat — albeit on a smaller scale — of the 2014 hack of Sony. U.S. officials have attributed that attack to North Korea, in retaliation for a film that mocked North Korean leader Kim Jong Un.

The Sony intrusion led to leaks of internal documents and emails. The fallout resulted in the departure of Amy Pascal, the head of the Motion Pictures Group of Sony Pictures Entertainment.

Last month, President Trump refused to certify that Iran was complying with its commitments under a deal designed to curtail that country’s nuclear program. The agreement was struck under the Obama administration, and Trump has called it “the worst deal ever.’’

The president, however, did not abandon the agreement. Instead, he left it to Congress to decide under what conditions nuclear-related sanctions should be reimposed, a move that would probably blow up the accord.

European officials have been visiting Congress to argue the nuclear deal is working and should be preserved.