Hassan Pisetskaya traveled about 1,100 miles from the city of Zaporizhzhia to the Slovakian capital of Bratislava on his own. All he had with him, according to Slovakian officials, was a passport in a plastic bag and a phone number written on his hand.

“Little Hassan is only 11 years old, but in his way he has shown huge determination, courage and fearlessness that sometimes adults don’t have,” wrote Slovakian interior minister Roman Mikulec.

After officials contacted family members in the country, Hassan waited for his mother, Yulia, to arrive from their city, with the two reuniting shortly after.

“I am very grateful that they saved the life of my child,” said Pisetskaya through an interpreter. “In your small country, there are people with big hearts.”

Hassan is not the only child to have evacuated Ukraine by themselves as the Russian invasion continues. UNICEF released a statement saying that “hundreds of thousands” of Ukrainian refugees are children, many of whom are unaccompanied or separated from their parents.

“Children without parental care are at a heightened risk of violence, abuse and exploitation,” UNICEF Executive Director Catherine Russell and U.N. High Commissioner for Refugees Filippo Grandi said in a joint statement. “When these children are moved across borders, the risks are multiplied.”

As more children enter neighboring countries either alone or with their parents, acts of kindness have been displayed by locals. One such story was that of a surprise party held at a Romanian refugee camp for 7-year-old Arina.

At least 28 children have died as a result of the Russian invasion.

“About one and a half million children are in the territories suffering from shelling and under siege, among them, there are orphans and children with disabilities who need immediate help,” said Daria Herasymchuk, Ukraine’s adviser on children’s rights.

Some parents, such as David and Iryna Korpiewski, are fighting to reunite with their children still in the country. Newsweek reported about the parents “on a rescue mission” to retrieve their 10-year-old daughter, Mary, from Zaporizhzhia, where a projectile set part of a nuclear power plant on fire on Friday.

“It’s been a constant battle,” David said, “but I’m determined to get my daughter here.”

Update 3/8/22, 11:03 a.m. ET: This article was updated with background information.