With the help of a nongovernmental organization called Save Ukraine, a Ukrainian grandmother traveled deep into enemy territory to rescue her 9-year-old grandson. To prepare for that mission, she learned how to craft a cover story, and says she had to travel through a minefield behind enemy lines.

According to the Ukrainian government, more than 19,000 Ukrainian children have been taken to Russia or Russian-occupied territory since the war began. Russia says they are evacuating Ukrainian children from the fighting in eastern and southern Ukraine and bringing them to safety. The International Criminal Court has charged Russian President Vladimir Putin and his top deputy in charge of children's rights, Maria Lvova-Belova, with the war crimes of unlawful deportation and transfer of children.

Why is Russia taking Ukraine's children

Mykola Kuleba, founder of Save Ukraine — a nonprofit helping rescue Ukrainian children — said Russia's plan is to destroy Ukrainian identity. 

"They brainwash them, indoctrinate them, Russify them," Kuleba said. 

According to Kuleba, Russia is stealing Ukrainian kids' future by erasing their past. 

Recreation or Re-Education? Ukrainian Children in Russian-Run Schools and Camps

Many Ukrainian children are put in Russian-run schools and camps. Several rescued Ukrainian children have come forward to share their experiences, revealing that what happens at these camps is less about recreation and more about re-education. They have recounted being subjected to repeated lies, including claims that Ukraine lost the war and that their parents did not want them.

"The Ukrainian kids are nothing to them," said Polina, speaking through a translator. "So to hurt us, they take our kids away."

How Nikita, Polina's Grandson, Was Taken

Nikita was living in a Ukrainian boarding school for children with special needs when the war broke out. According to a teacher at the school, Russian authorities ordered all 86 children to be transferred deeper into Russian-controlled territory.

Polina, who requested anonymity due to safety concerns, only discovered that her grandson had been moved by chance.

"I came home after work, I opened Instagram, and there was a picture of my child, Nikita, with a caption, 'Russia is taking children,'" she said.

The grandmother later learned that Nikita had been moved at least three times over the course of eight months, including to an orphanage in Russia.

"The Russian Federation stole him. They abducted him," Polina revealed.

For months, Polina, who had helped raise Nikita, struggled to sleep and lost the will to work.

"I didn't even want to live because I had no one to live for," she said.

That's when she discovered Save Ukraine on Facebook.

Saving Ukraine's children

Save Ukraine has helped rescue over 200 children so far, including Polina's grandson. Kuleba was Ukraine's Presidential Commissioner for Children's Rights for nearly eight years and began running undercover rescue missions last fall.

Polina, who moved to Poland before the war to work so she could support Nikita, caught a 20-hour train to meet the Save Ukraine team in Kyiv. She traveled light, but she carried the weight of a grandmother's worry.

"He means everything to me," she said. "He is my air, my sky, my water. I live for him, he is my life. I love him very much."

Only women go on Save Ukraine's rescue missions because the men need to stay behind and fight. The mothers and grandmothers get a safety briefing from Save Ukraine before their dangerous journey.

"We explain [to] them that Russians will intimidate you," Kuleba said. "They will be doing everything to stop you, to provoke you. That's why you should focus on your child. Your goal is to take your child and not be afraid."

The night before she left to find Nikita, Polina gathered gifts for her grandson.

She and Save Ukraine had created a plan to get past border checkpoints near the school where Nikita was being held in Russian-occupied territory. Polina managed to call in while "60 Minutes" was filming with the Save Ukraine team.

"I was moving there in a car throughout that minefield," Polina said through a translator. "There was a heavy smell of dead bodies there. It's so scary."

While on the road, the only help Polina and others like her have is a secret network organized by Save Ukraine.

Struggle to bring Nikita home

To get past border checkpoints on the way to the school, Polina pretended to be an aid worker. Her driver secretly recorded as she walked into the school where her grandson was being held.

"The director asked me, 'how did you get here?' I told him: 'I'm a volunteer. I came from Poland and I brought you some humanitarian aid,'" Polina said. "I needed to say something, to be able to see Nikita and figure out a way to get him out of there. This was the only way to do it."

Once inside, Polina presented a Ukrainian document authorizing her to take her grandson home, but said the Russian-installed director refused to release Nikita. She feared they were trying to give him a new life in Russia. Polina feared the Russians were on the verge of giving her grandson to a Russian family.

Last year, President Vladimir Putin signed a decree to make it easier for Ukrainian orphans and children without parental care to receive Russian citizenship, allowing them to be adopted by Russian families.

Polina showed documents to "60 Minutes" that led her to believe that Nikita was about to be adopted by a Russian family.

She said the school called her Ukrainian document fake and demanded a DNA test to prove Nikita was her grandchild.

For 70 days, Polina refused to back down. Finally, she was brought into a room where she was reunited with Nikita. Lvova-Belova and Russian cameras were there, too. The cameras rolled as Lvova-Belova handed Nikita gifts. Polina said Lvova-Belova also asked her if she'd like to stay in Russia and offered her money and a car.

"I don't need anything. I have everything,'" Polina said.

Lvova-Belova insists Russia does not put Ukrainian children up for adoption and that it makes every effort to return them. On social media, she called Polina and Nikita's reunion a joy and wished them a "happy life."

Moving on

Finally reunited, Polina and Nikita began the long trip back to safety, driving day and night for a week. The Save Ukraine team greeted the pair when they arrived in Poland.

Polina and Nikita have made the decision to temporarily reside in Poland until the war comes to an end. In the meantime, the grandmother is in the process of applying for Ukrainian guardianship of her grandson.

While Polina is bravely sharing her story and raising awareness, Nikita has his own plans for spending time with his grandmother.

"I want to play with her," he expressed through a translator.