Iranian hackers used Facebook to create elaborate fake personas with the purpose of getting Americans in the military, defense, and aerospace industries to fall for phishing schemes so that the hackers could access personal and classified information, Facebook said on Thursday.

The hackers also targeted defense personnel in the U.K. and Europe.

The Iranian spying campaign began last year. Facebook took down “fewer than 200 operational accounts”, according to Mike Dvilyanski, Facebook’s head of cyber-espionage investigations.

This is another attack on the U.S. but this time, Iran didn’t target infrastructure or large corporations but the military and defense industry.