While most Tajiks in Syria are fighting alongside the Islamic State (IS) group, they are also present in at least two other Islamist factions in Syria, one of them in a leadership role.
An ethnic Tajik known as Abu Ibrakhim Khorasani has been appointed the new commander of the formerly Chechen-led faction Jaish al-Muhajireen wal-Ansar (JMA).
And two Tajiks say they are fighting alongside the Crimean Jamaat, a breakaway group from JMA.
Little is known about the background of Abu Ibrakhim, who was appointed the commander of JMA after the group's former leader, Salakhuddin, an ethnic Chechen from Georgia's Pankisi Gorge, was ousted last month.
A JMA-affiliated account on Facebook described Abu Ibrakhim as a Russian-born Tajik.
Abu Ibrakhim's chosen nom de guerre of Khorasani could provide another clue about his origins.
Islamist militants, both from IS and other groups, usually take the final part of their pseudonyms from their hometown or home region. Tajik militants usually call themselves "al-Tajiki" or "al-Tochiki" -- but Abu Ibrakhim's name of Khorasani is taken from a reference to a historical geographical area encompassing Afghanistan, parts of Central Asia, and other neighboring countries.
It is possible that Abu Ibrakhim's origins lie in the area of northwestern Tajikistan that was part of the old Khorasan region, or it could mean that his family origins are from Afghanistan, where Tajiks are the second-largest ethnic group.
But it is more likely that Abu Ibrakhim chose the name to show off his knowledge of the Khorasan hadith, which is central to Islamist ideology and which talks of a Muslim army advancing from "Khorasan" to Jerusalem.
Apart from his name, little else is known about Abu Ibrakhim except his reputation as an effective military commander within JMA, a group based in Syria's northern province of Aleppo. Since early 2014, JMA has mainly fought alongside the main Syrian Islamist factions including Al-Qaeda's Syrian affiliate Jabhat al-Nusra; it was Abu Ibrakhim who led JMA fighters in an April offensive alongside Nusra to capture the Syrian town of Jisr al-Shughur in Idlib province.
Until Abu Ibrakhim's appointment as commander, JMA was dominated by North Caucasus militants who had pledged allegiance to the Caucasus Emirate (CE) Islamist insurgent group. While many of those CE-aligned fighters left when JMA's former leader was deposed, Abu Ibrakhim appears set to continue the group's alliances with Jabhat al-Nusra and other Islamist factions.
Tajiks In The Crimean Jamaat
Two ethnic Tajiks, who call themselves Abdullah Tajik and Abu Umar al-Tajiki, are fighting alongside a smaller group known as the Crimean Jamaat.
Based in Aleppo province, the Crimean Jamaat was originally a part of JMA until it split off from that group sometime in 2014. Despite its name, not all of its members are ethnic Crimean Tatars; Abdullah Tajik has written on his VKontakte account that the group has a Russian commander and a Syrian military commander.
While the Crimean Jamaat has not openly declared its allegiance to any group, Abdullah Tajik posted a photograph of himself in February holding a black banner that read "The Taliban In The Land Of Sham ["the Levant"]."
Abdullah has also posted a photograph of himself holding what appears to be a AK-74M rifle, which he claimed on social media cost him around $3,400.
Abu Umar al-Tajiki, who claims on his Odnoklassniki account to be 22 years old and based in Aleppo, has posted photographs and videos of the Crimean Jamaat's training exercises as well as an image of the group's flag.
Abu Umar has also announced on Odnoklassniki that he is seeking a second wife.
Growing Number Of Tajiks In IS
Tajikistan has acknowledged that the number of Tajiks fighting in Syria and Iraq has grown but has only spoken publicly of Tajiks fighting alongside IS.
On June 20, Tajik Interior Minister Ramazan Rakhimzoda said that the number of Tajiks fighting alongside IS had increased to 500.
"Their surnames are known, the prosecutor-general has initiated criminal cases in absentia," Rakhimzoda was quoted as saying by Russia's TASS news agency.
More than 100 of those fighting in Syria and Iraq have been killed, Rakhimozoda added.
The interior minister called on his colleagues "not to let our sons die for foreign values, false ideals."
"It is the duty of every police officer to strengthen outreach work among the population, and involve representatives of the Muslim clergy [and] local activists," Rakhimzoda added.
Edward Lemon of the University of Exeter in the U.K., who tracks Tajik militants in Syria and Iraq, said the government's figure "appears to be relatively accurate."
"The number has been creeping up at a steady rate, from 200 back in 2014 to 386 in May and now 500. This has been reflected in documented reports of Tajiks fighting and dying in Syria and Iraq," Lemon told RFE/RL.