The campaign of Republican US presidential candidate Donald Trump said on Saturday some of its internal communications were hacked and blamed the Iranian government, citing past hostilities between Trump and Iran without providing direct evidence.

The campaign statement came shortly after news website Politico revealed it began receiving emails in July from an anonymous source offering authentic documents from inside Trump’s operation, including a report about running mate JD Vance’s “potential vulnerabilities.”

“These documents were obtained illegally from foreign sources hostile to the United States, intended to interfere with the 2024 election and sow chaos throughout our Democratic process,” Trump campaign spokesperson Steven Cheung said in a statement.

Reuters has not independently verified the identity of the alleged hackers or their motivation.

The Trump campaign referred to a Friday report from Microsoft researchers that said Iranian government-tied hackers tried breaking into the account of a “high-ranking official” on a US presidential campaign in June. The hackers had taken over an account belonging to a former political advisor and then used it to target the official, the report said. That report did not provide further details on the targets’ identities.

A Microsoft spokesperson declined to name the targeted officials or provide additional details after the report was published.

Iran’s foreign ministry and its United Nations representative did not immediately respond to requests for comment.

On Friday, in response to Microsoft’s findings, Iran’s mission to the U.N. in New York told Reuters that its cyber capabilities were “defensive and proportionate to the threats it faces” and that it had no plans to launch cyberattacks.”The US presidential election is an internal matter in which Iran does not interfere,” Iran’s mission to the U.N. said.

The former president had tense relations with Iran while in office. Under Trump, the United States killed Iranian military commander Qassem Soleimani in 2020 and withdrew from the Iran nuclear deal.

“The Iranians know that President Trump will stop their reign of terror just like he did in his first four years in the White House,” Cheung said.

Trump survived an assassination attempt in July. While there have been no suggestions that the suspect was linked to Iran, CNN reported last month that the US had intelligence about an Iranian plot against Trump. Iran has denied such charges.

Late last month, a senior intelligence official told reporters in a briefing that Tehran and Moscow maintain their same presidential preferences as in past cycles, where Iranian operatives will attempt to tear down the Republican ticket while Russia has made efforts to smear Democrats, according to prior intelligence community assessments.