As the Islamic State group loses territory in Iraq and Syria, many IS foreign recruits are believed to be returning to their home countries.
Due to loss of territory and plunging revenues, the terror group is struggling to pay its foreign fighters' wages. Deutsche Welle, Germany's international broadcaster, reports that this has forced some foreign fighters to return home. This trend could be most pronounced among militants in Central Asia.
Russian expert Andrey Serenko says Central Asian governments are preparing for the return of their militant citizens.
"Real numbers could be different [unknown], but the truth is that there is a stream of returning militants," Serenko said. "For example, whole families who left Kyrgyzstan are now returning. Special measures have been taken, such as arranging meetings with psychologists, religious scholars and even former militants from Syria.
"Those who have returned are in the several hundreds, and given the recent situation in Syria, this number is expected to increase," Serenko added.
According to some experts on the role of Central Asian combatants in the Middle East, militants from Kyrgyzstan, Kazakhstan and Tajikistan are more likely to leave Islamic State and return home, whereas Uzbeks are likely to join other like-minded groups in the same region. That could be due to the Uzbek government's no-holds-barred crackdown on what it sees as extremism.
Uzbek veterans of Islamic State "could either settle in Turkey, or move to northern Afghanistan to join other extremist groups," Serenko said.
The Tashkent government has not officially said anything about Uzbek citizens fighting in Syria. Most of them reached the Middle East via other countries, such as Russia or Turkey. Millions of Uzbek citizens work abroad as migrant laborers, most of them in Russia.
Unemployment, lack of religious freedom, and continuous repression are the main factors that persuade young Uzbeks to take the path of jihad, according to Rahrom Hamroev, a human-rights activist based in Russia.
"If migrants are expelled from Russia, it merely increases the number of militants, because they have no other place to go," Hamroev said. "In Uzbekistan, all they can find is unemployment and a lack of human rights."
Uzbeks fighting in Syria are estimated to number between 500 and several thousand.
Muhammadsolih Abutov, a religious activist and imam from Uzbekistan who currently lives abroad, says several Syrian groups have Uzbeks in their ranks.
"There are many jihadists from the region. Some are fighting [with unspecified groups] against Assad; others are with Daesh [another name for Islamic State], while some are in Jabhat al-Nusra," Abutov said.
"It is not true to say that their Central Asian roots will unite them all," the exiled Uzbek activist adds. "They do not have a common cause such as Turkestan [the notion of a pan-national state grouping all ethnic Turkic people in Central Asia]. They are divided and fighting against each other."
