Afghan Shiite militants have been fighting on the Assad regime's side for some time, and the scope and strategic purpose of Iran's involvement is becoming increasingly clear.

On May 22, the Wall Street Journal reported that Iran's Islamic Revolutionary Guard Corps (IRGC) was recruiting Afghan Shiite refugees to fight in Syria, promising them a salary of $500 per month as well as Iranian residency papers. The article noted that reports of funerals for such fighters began to emerge in November 2013, and that they had originally been recruited to offset losses among IRGC operatives in Syria. Yet the phenomenon of Afghan Shiite combatants fighting on Bashar al-Assad's side is hardly a new development, and their increased involvement in the war merits closer scrutiny given the potential implications for Syria and the future of Iran's regional and sectarian ambitions.

BACKGROUND

As early as October 2012, elements associated with the opposition Free Syrian Army claimed to have captured an Afghan Shiite fighter named Mortada Hussein. He was later interrogated by the rebels on a short YouTube video clip. The presence of other such fighters became a more regular and public subject beginning in spring 2013, around the time that Lebanese Shiite jihadist group Hezbollah announced it had deployed forces to Syria. Subsequently, opposition and regime social media circulated unconfirmed images of uniformed Afghans posing together and holding weapons. In many cases, their faces -- which tended to be ethnically distinct -- were clearly shown, and the fighters were described as "martyrs." Yet these fallen Afghans were never named.

In July 2013, however, a martyrdom poster emerged naming Safer Muhammad as one of the Afghans who had been killed. The gold-framed poster featured the flags of Hezbollah, the Syrian regime, and Afghanistan.

ORIGINS OF IRAN'S AFGHAN LEGIONS

The Afghan Shiites fighting in Syria have come from three main sources. First is the contingent already residing in Syria before the war, a number of whom lived near Sayyeda Zainab, a prominent Shiite shrine located south of Damascus. According to researcher Ahmad Shuja, some 2,000 Afghan Shiites, mainly belonging to the Persian-speaking Hazara ethnic group, took up residence in Syria before hostilities broke out. As with Hazara refugees in other countries, many of them had fled Afghanistan after suffering regularly at the hands of the Taliban. Yet once the war started, many were once again reportedly targeted for attacks based on their sectarian identity, quickly becoming internally displaced persons. Some of them joined the fighting; for example, Ali Salehi, a Hazara reportedly residing in Syria, was killed during hostilities in the Damascus area.

Fighters from this refugee population appear to have followed an organizational model similar to Liwa Abu Fadl al-Abbas (LAFA), the main pro-regime Shiite brigade in Syria. LAFA's original core consisted of Iraqi Shiite refugees from the Sayyeda Zainab area who assembled in a popular-committee format; their avowed justification for fighting was to defend the Shiite shrine. Iranian-backed recruits and trained fighters from established organizations such as Asaib Ahl al-Haqq (AAH), Kataib Hezbollah, and Lebanese Hezbollah later helped expand the brigade and build its combat abilities.

A second contingent of Afghan Shiite fighters hails from Iran; according to Iranian government-backed newspapers and Afghan Shiite sources, they are the largest such contingent. Many of these recruits were originally refugees in Iran, which is home to around half a million Hazaras; a 2010 Stimson Center report noted that a third of these refugees "have spent more than half their life in Iran." Public funerals held in the Islamic Republic in November-December 2013 indicate that Afghan Shiite fighters came from cities throughout the country, including Isfahan, Mashhad, Tehran, and Qom. One young "martyr," Reza Ismail, had attended Iran's University of Mashhad, and a photo reportedly taken in Syria showed him holding an M4-type carbine. Apparently, he was beheaded by Sunni jihadist rebels.

A third and more debatable source of Afghan Shiite fighters is refugee populations in countries other than Iran and Syria. In April 2013, officials in Afghanistan announced that they would look into reports of Afghan nationals fighting for Assad. And just last month, Kabul called on Tehran to not recruit its nationals to fight in Syria. If direct Iranian recruitment were proven, Kabul threatened to file a complaint with the UN High Commissioner for Refugees. Yet real evidence of direct recruitment in Afghanistan has yet to surface.

In another case, an unnamed fighter pictured holding a PKM machine gun was claimed to be an Afghan Shiite refugee who had been granted asylum in Australia before joining the war in Syria. But this claim has not yet been proven.

AFGHAN SHIITE SPECIAL GROUPS

Initially, Afghan Shiite combatants were present in the network of brigades associated with LAFA. When some of these fighters were killed in action, they were specifically named as LAFA members; photos have also shown Afghan Shiites wearing the group's insignia on their combat fatigues.

These and other links to the most well-known Shiite brigades are a continuing reality, but the November-December funerals in Iran indicated that the nature of Afghan Shiite involvement in the war had shifted. The ten fighters who were mourned at those funerals were declared to be members of a new militant organization called Liwa Fatemiyoun. Although this brigade has since claimed to recruit more than just Afghan Shiites, materials released by its supporters emphasize the targeting of that particular constituency.

Both Liwa Fatemiyoun and Tehran have also denied direct Iranian government involvement in the group's activities, but such claims are absurd. Not only have the group's recruitment efforts been executed in Iran, but funeral processions for fallen members have regularly included uniformed IRGC soldiers as well as posters featuring the logo of Iran's official Foundation of Martyrs and Veterans Affairs.

Despite forming their own group, Afghan Shiite militants continue to coordinate and fight side-by-side with other pro-regime Shiite groups on a regular basis. For example, photos released on social media sites belonging to Liwa Fatemiyoun showed one Afghan fighter with two militants from AAH. Similarly, an Iranian newspaper report claimed last month that Afghan Shiite fighters had a presence in AAH and other Shiite militias such as Liwa Dhulfiqar. This presence has allowed such fighters to take part in major engagements throughout Syria, reportedly including April clashes in the Damascus area.

The development of special groups for Afghan Shiite fighters did not end with Liwa Fatemiyoun, which is now apparently incorporated with another relatively low-profile group called Hezbollah Afghanistan. Material put out by the two groups has been similar, with both claiming the same members and martyrs. While Hezbollah Afghanistan has not yet made official headlines, it has developed its own symbolism and expanded its presence in the cloistered ranks of IRGC-associated online social networks.

IRAN'S STRATEGIC THINKING

The Afghan Hazara Shiite community was a logical target for Iranian recruitment in Syria's war. Tehran has a track record of exploiting Shiite populations that it can directly influence due to its geostrategic, religious, and historical position. Given the long-term population of Afghans in Iran, Tehran may view the war as an opportunity to extend its influence over disparate Shiite elements and push its leadership agenda. Furthermore, the use of ethnically diverse fighters can be used to demonstrate wide Shiite support for the Iranian-organized armed defense of Assad, with the presumed goal of legitimizing Tehran's approach.

As noted in other reports, it is also clear that the IRGC and its proxies are taking casualties in Syria and require replacements. Afghan Shiites, many of whom had formative experiences with harsh sectarian wars in Afghanistan, are perfect candidates to fight Sunni rebels in Syria, though their actual battlefield effectiveness remains to be determined. At the very least, their growing presence is likely providing a much-needed respite for Iranian forces and their proxies.

Finally, Iran might reap other residual benefits from training, equipping, and seasoning these units. As the United States begins its broader pullout from Afghanistan, Tehran could decide to reorient its new network of Afghan proxies eastward, with the goal of asserting broader influence among Afghanistan's often fractious Shiite communities.

Phillip Smyth is a researcher specializing in Shiite Islamist groups at the University of Maryland's Laboratory for Computational Cultural Dynamics. His work on these groups can be found on the blog Hizballah Cavalcade.