Facebook has dropped 51 accounts, 36 pages, and seven groups after the cybersecurity firm FireEye revealed they were fake accounts originating in Iran.
Three Instagram accounts were also deactivated.
The FireEye report Tuesday says the phony accounts pretended they came from the United States and impersonated legitimate Middle Eastern news sources to push a pro-Iranian agenda.
Posts written in both English and Arabic included discussions about American and British politics, Islam, Arab minorities, and the influence of Saudi Arabia. The posts represented both conservative and liberal points of view.
One post said the best way to honor the memory of slain Saudi journalist Jamal Khashoggi was for the U.S. to stop sending aid to the Saudi coalition fighting Iranian-backed rebels in Yemen.
The fake posters even succeeded in getting letters to the editors published in a number of U.S. newspapers, includingThe Los Angeles Times and The New York Daily News.
The author of the FireEye report, Lee Foster, was careful not to directly blame the Iranian government for the illegitimate accounts, saying the investigation is continuing.
Facebook says it is also investigating and is sharing information with law enforcement.
"We're constantly working to detect and stop this type of activity because we don't want our services to be used to manipulate people," Facebook said.
It added it canceled the suspect accounts for their behavior, and not because of content.