U.S. intelligence officials have confirmed that Iran was behind the recent cyberattack on Donald Trump’s presidential campaign. In a joint statement, the FBI and other federal agencies revealed that Iran sought to interfere in the U.S. election to “stoke discord and undermine confidence in our democratic institutions.”

On August 10, the Trump campaign initially pointed to Iran as the culprit behind the breach of its internal communications, which Iranian officials denied. Sources close to the investigation, speaking to CBS News, also believe that Iranian hackers targeted Kamala Harris’s campaign.

“The intelligence community is confident that the Iranians, through social engineering and other efforts, sought access to individuals with direct connections to the presidential campaigns of both parties,” the statement said. It noted that such activities, including data thefts and leaks, aim to influence the U.S. election process.

Reports indicate that the Trump campaign was targeted by a spear-phishing email—a type of message designed to appear legitimate to trick the recipient into clicking on a malicious link. The Harris campaign reported a similar attempt, although it was unsuccessful.

The joint statement from the FBI, the Office of the Director of National Intelligence, and the Cybersecurity and Infrastructure Security Agency stressed that these tactics are “not new” and have been employed by both Russia and Iran in previous U.S. elections.

It remains uncertain what, if any, information was stolen during the hack. Trump asserted that the hackers only accessed publicly available data. However, reports from The New York Times, Politico, and The Washington Post suggest that confidential information, including details on the vetting of Trump’s running mate JD Vance, was leaked. These outlets have not provided specific details.

U.S. officials noted that Iran aims to influence elections it views as particularly consequential for its national security. The intelligence agencies also reported increasingly aggressive Iranian activity during this election cycle, heightening concerns over the threat posed by Iranian hackers.

Microsoft recently highlighted “significant influence activity” linked to Iran, and before exiting the race last month, Joe Biden’s campaign was similarly targeted by Iranian hackers, as was Trump’s, according to Google.