Afghan refugees in Iran have a choice between deportation or fighting in Syria to obtain a residency permit. A few months after Iran asked Hezbollah to join the fighting in Syria alongside Mr. Assad’s forces, it began raising other Shiite militias. The Fatemiyoun Division (formerly Brigade), a militia of Shiite Afghan refugees, was formed around early 2014 and trained by both the Revolutionary Guards and Hezbollah veterans. Its strength has been estimated at 8,000 to and 14,000 men. The Iranian authorities maintain the fighters are volunteers.