A joint investigation by social network Facebook and security vendor FireEye has unveiled a large online propaganda campaign promoting Iranian political interests via social media.
In total, Facebook said it had removed 652 pages on its network and on social image and video sharing site Instagram that it said originated in Iran, and were responsible for coordinated inauthentic behaviour, targeting people in the Middle East, Latin America, United Kingdom and the United States.
Accounts set up on Facebook and Instagram by "Liberty Front Press", a bogus media organisation run from Iran, had tens of thousands of followers. In one case, a Middle East politics page had 813,000 accounts follow it.
The Iranians spent over US$12,000 (A$16,300) on Facebook and Instagram ads as well. These were paid for in US and Australian dollars, along with Turkish lira and Indian rupees, Facebook said.
Liberty Front Press has been active on other social media sites too, including Twitter, Google Plus and YouTube, with thousands of messages posted, a report FireEye shared with iTnews showed.
FireEye discovered that US Journal, described as a "genuinely independent online media outlet" used a phone number with the Iranian +98 country code on its Twitter account.
One journalist listed as a writer on US Journal appears to be genuine and exist, FireEye said.
However, two others, "Elizabeth Tacher" (@BethTacher on Twitter) and "Liam Jay Campbell" (@LiamJayCampbel1) appear to be fabricated personas with profile pictures taken from actors and stock photo libraries.
FireEye also discovered what appears to be a fake non-governmental organisation, "Real Progressive Front" that claimed to employ the same individuals as US Journal, and "The British Left" site which also passes itself off as an NGO.
Targeting Latin American web users, the Iranians set up a site for "Instituto Manquehue" that claimed to be an independent civic organisation but which used an email for the domain registration found on another site promoting Shia Islam.
The themes promoted were pro-Iranian and pro-Palestinian views, and support for UK Labour Party leader Jeremy Corbyn.
American president Donald Trump, who pulled his country out of the nuclear anti-proliferation deal with Iran, was attacked by the social media accounts.
US senator Bernie Sanders who sought nomination as the Democratic Party's presidential candidate in 2016, was also targettted by the Iranian social media accounts.
They also promoted anti-Israel and anti-Saudi Arabia themes, as the two countries are Iran's main adversaries in the Middle East.
FireEye noted that the accounts were active during the Iranian working week, tweeted topics relevant to the country and used hashtags such as #Arbaeen, referring to a Shiite religious holiday, FireEye said.
Asides from using Iranian +98 phone numbers, the accounts also posted from internet protoocol addresses allocated to networks in the Middle Eastern country, FireEye said.