The estimate the number of people inside the last IS bastion, a patch of half a square kilometre on the banks of the Euphrates River, at anything from a few hundred to several thousand.
The arrest of two men with ties to IS accused of plotting to attack police in Satbayev is the latest move by Kazakh authorities against terrorism.
Kazakhs who have seen the true face of 'Islamic State' could help prevent extremism and radicalisation at home, analysts say.
Alexandr Bekmirzaev converted to Islam in Uzbekistan about 20 years ago but became 'radicalised' and 'brainwashed' after going to Syria in 2013.
The operation brought home 47 Kazakh nationals -- including 11 women and 30 children -- from Syria, according to the government.
It is essential to quickly rehabilitate, educate and reintegrate into society children returning from conflict zones, analysts say.
A government working group will work with the relatives of those who have left Kazakhstan for Syria and Iraq to bring them home.
The number of crimes related to terrorism and extremism in Uzbekistan this year decreased by more than 65% compared to last year, according to officials.
The extremist private military contractor, founded by an Uzbek, has been operating in Syria and is seeking to expand, analysts warn.
Ongoing arrests and extraditions of terrorism suspects send a clear message to those who are considering throwing their lives away for the sake of false ideals, observers say.