Twitter said on Friday it had permanently banned what it called a "fake" account thought to be connected to the office of Iran's supreme leader, shortly after a posting that seemed to threaten former President Donald Trump.

In the image posted late Thursday by the account linked to Ayatollah Ali Khamenei, Trump is shown playing golf in the shadow of a giant drone, with the caption "Revenge is certain" written in Farsi.

In response to a request for comment from The Associated Press, a Twitter spokesman said that the tweet had violated the company's "abusive behaviour policy," and that the account had violated its "manipulation and spam policy."

In a later statement, he said Twitter had determined the account was "fake," without elaborating how it came to the conclusion.

The suspended account, Γåòkhamenei--site, linked Khamenei's own website and frequently posted excerpts from his speeches and other official content.

Other accounts thought to be tied to Khamenei's office that did not tweet the golf-drone photo, including his main English language account, remained active. The photo had also featured prominently on the supreme leader's website.

Earlier this month, Facebook and Twitter cut off Trump from their platforms for allegedly inciting the assault on the U.S. Capitol, an unprecedented step that underscored the immense power of tech giants in regulating speech on their platforms. Activists soon urged the companies to apply their policies equally to political figures worldwide in order to combat hate speech and content that encourages violence.

The warning in the caption referenced Khamenei's remarks last month ahead of the first anniversary of the U.S. drone strike that killed Iranian Revolutionary Guard general Qassem Soleimani in Baghdad. In his speech, Khamenei did not call out Trump by name, but reiterated a vow for vengeance against those who ordered and executed the attack on Soleimani.

"Revenge will certainly happen at the right time," Khamenei had declared.

Iran blocks social media websites like Facebook and Twitter, and censors others. While top officials have unfettered access to social media, Iran's youth and tech-savvy citizens use proxy servers or other workarounds to bypass the controls.

Soon after Trump's ban from Twitter ignited calls to target tweets from other political leaders, the company took down a post by a different Khamenei-linked account that pushed a COVID-19 vaccine conspiracy theory.

Khamenei, who has the final say on all state matters in Iran, had claimed that virus vaccines imported from the U.S. or Britain were "completely untrustworthy."