A hacking network believed to originate in Iran used social media to coordinate an ongoing, cyber espionage campaign against high ranking officials in the public and private sector in the U.S., Israel and the U.K., according to an iSIGHT Partners report released this week. The private intelligence firm believes the campaign has been operating undetected since 2011.

The report warns that Iranian “threat actors” are using more than a dozen fake personas on social networking sites like Facebook, Twitter, and LinkedIn to target at least 2,000 individuals, including senior U.S. military and diplomatic personnel, congressional personnel, Washington D.C. area journalists, U.S. think tanks, defense contractors in the U.S. and Israel. The hackers’ goal appears to be to covertly obtain log-in credentials to the email systems of their victims.

“This is unlike anything we’ve seen in terms of the lengths these guys have gone to create credible personas and get past the filters people have now,” Patrick McBride, iSIGHT’s vice president for marketing, told Bloomberg.

The Iranian hacking team created fake personas claiming to work in journalism, government, and defense contracting, the report states. They went to elaborate lengths to add credibility to these fake accounts, creating, for instance, a fictitious journalism website, newsonair.org, that plagiarizes news content from legitimate media outlets.

After using these credible personas to “friend” target victims, the accounts were then exposed to  “spear-phishing” messages, where links which appeared to be legitimate asked recipients to log-in to false pages, thus capturing credential information. It is not clear at this time how many credentials the attack has captured to date, according to the report.

“Adversaries such as these are increasingly adept at finding and exploiting opportunities to carry out cyber espionage, even when lacking sophisticated capability,” iSIGHT Partners said. “[The hacking campaign’s] success is largely due to its patience, brazen nature, and innovative use of multiple social media platforms.”