The center in Aqtau, where the returnees are placed upon their arrival, is off limits to the media, the public, and even the relatives of the returnees.
But officials familiar with the rehabilitation program told RFE/RL that in Aqtau the returnees undergo medical tests and receive treatment or surgeries they require.
Back To Normal Life
The center also employs specially trained psychologists and religious figures, who conduct meetings and consultations with the returnees.
Meanwhile, children attend special classes with teachers and child-psychology specialists, while adults also face background checks and interviews by security services.
Those cleared by security services to return to normal life are allowed to move back to their home regions within several weeks and register with local authorities.
Dozens of others have been transferred to detention centers to face terrorism-related charges.
Operation Zhusan (which means sagebrush) took place in three rounds between January and May and brought home a total of 516 Kazakh citizens, including 357 children, according to official figures.
The government said 47 people returned in the first round in January and another 231 Kazakhs were flown home from Syria in the second round in early May.
The third and final round took place at the end of May with 238 women and children brought back.
The government says there won't be any more such operations in the future. It is not known if there are any more Kazakh nationals left in Syria or Iraq, the two countries within which Islamic State controlled swathes of territory until collapsing under attack from U.S.-led forces in late March.
In July 2018, Kazakhstan's National Security Committee said more than 800 Kazakh nationals had left for Syria and Iraq since 2013 to join IS.
A lot of those fighters and their families were killed in air strikes and fighting since IS first acquired territory in 2014.
Many Kazakh fighters and women also became disillusioned and returned home long before the Zhusan operation began.
Still A Security Threat?
At least 27 people, including five women, who returned to Kazakhstan as part of the Zhusan operation have been arrested on terrorism-related charges.
Erlan Karin, an adviser to Kazakh President Qasym-Zhomart Toqaev, says one of the most frequently asked questions about the returnees is whether they will pose a security threat in the future.
Kazakhstan, where some 70 percent of its more than 18 million population is Muslim, has seen several deadly attacks blamed on religious extremists.
A suicide attack near a regional headquarters of the National Security Committee in Aqtobe in 2011 was the first incident the government linked to Islamic extremism.
Aqtobe was the scene of deadly violence again in 2016 when a military unit came under attack.
Authorities said the assault was carried out by some 20 Islamist radicals who raided two gun stores before targeting the soldiers.
In 2013, a video emerged purportedly showing a Kazakh family of 150 people, including many children, preparing for jihad in Syria. They urged others in Kazakhstan to join them.
Critics of the government's repatriation program argue that those brought back from Syria should not be trusted.
Those who really regretted joining IS came back a long time ago, but these people waited until the last minute, until IS collapsed, says Nurlan, a student in Almaty who didn't want to give his full name.
They returned because they had no other choice, Nurlan added.
Presidential adviser Karin says any potential security threats would have been much greater if Kazakhstan left its citizens, especially the women and children, stranded in refugee camps in Syria.
For example, there is a risk of these women and children being exploited by radical extremist groups for various [purposes], Karin told RFE/RL on June 17.
Karin says the authorities, communities, and families need to continuously work with the returnees, especially with children, to prevent any threats in the future.
Now that they're safely back in Kazakhstan, there is an opportunity to constantly work with the children, to influence them, Karin said.
Karin said some 70 percent of the repatriated children are under the age of six, and many of them were born in Syria. They have never been to school and can't read, write, or do arithmetic, he said.
According to Karin, there are many orphans among the children, but their extended families and relatives have been granted custody.
Not a single child that returned from Syria was left without family support, Karin said. All were taken in by their relatives.
Aigerim Toleukhan, a Kazakh journalist who focuses on political issues, emphasized the challenges in the rehabilitation of the deeply traumatized children whose only experiences in life so far were fighting, air strikes, and the death and destruction that follows.
Even with the help of professionals they will need many years [to be able] to live like normal children, Toleukhan told RFE/RL.
Creating Opportunities And Hope
Like Zarina in Aqtobe, who married at the age of 18, many women repatriated from Syria have no skills or profession.
As part of the reintegration process, local authorities have organized short-term courses in which returnees can learn new skills to help them earn a living.
Several women who returned from Syria in January have completed the courses and found jobs as hairdressers and beauticians.
Zarina says she hasn't yet decided what to do with her life.
She and her children live with her parents and receive financial support from the relatives of her husband, who was killed in Syria.
The returnees have no legal obstacles to get jobs or study in universities, although they will be closely monitored by authorities for many years to come.
The government says the children born in Syria to Kazakh citizens are being given Kazakh passports.
Repatriation Around Central Asia
Most of Kazakhstan's neighbors in Central Asia have taken a similar approach in dealing with the issue of their citizens in Syria and Iraq who joined IS.
In late May, Uzbekistan announced that it had flown home 156 Uzbeks from Syria and Iraq.
The government in Tashkent said it will create "the necessary conditions for their return to a normal, peaceful life and integration into society, access to educational and other social programs, including through the provision of adequate housing and employment."
Tajikistan has offered an amnesty to its citizens who voluntarily return home from Syria and Iraq and denounce IS. It recently brought back dozens of Tajik children whose mothers are jailed in Iraq for their ties to IS.
Kyrgyzstan announced in February that the government began working to clarify the number of Kyrgyz citizens in Syria and Iraq. It came after several Kyrgyz women in Syria pleaded with Bishkek to help them come back home.
Experts warn that in order to prevent security threats in the future, the governments in Central Asia need to address the major root causes of the problems.
All of the driving reasons that caused a small number to fight abroad -- injustice, marginalization, repression -- still exist. Young people will seek new ways to express this frustration, sometimes using violence, said Edward Lemon, a fellow at the Daniel Morgan Graduate School of National Security in Washington, D.C.
Kazakhstan, Uzbekistan, Tajikistan, and Turkmenistan -- which are ruled by authoritarian leaders -- have received especially harsh criticism by rights organizations for restricting basic freedoms, human rights, and religious practices.
Those governments also don't tolerate dissent and crack down on independent media and opposition parties.
In energy-rich Kazakhstan, many ordinary people live in poverty, as the burgeoning oil wealth has failed to trickle down to them and has widened the gap between rich and poor.
But Zarina feels fortunate to have a second chance.
"I regret leaving my homeland -- and it's a regret I will have my entire life," she said. "Despite our mistakes, Kazakhstan welcomed us. I do not have words to express my gratitude."
Radio Free Europe:Copyright (c) 2015. RFE/RL, Inc. Reprinted with the permission of Radio Free Europe/Radio Liberty, 1201 Connecticut Ave NW, Ste 400, Washington DC 20036.