Pale and grimy from living in a dank, dark basement for nearly a year, the teenager and his weeping mother emerged to the sound of pounding artillery and headed to a waiting armored police van that would whisk them to safety.

Russian forces were not far from their battered front-line town of Avdiivka in eastern Ukraine, where shells fall daily, ripping through buildings, smashing cars and leaving craters.

Dark, curly hair peeping out from beneath his hoodie, 15-year-old Oleksii Mazurin was one of the last youths still living there. After his evacuation Friday, another 13 remained, said police chief Roman Protsyk.

Before the Russian invasion of Ukraine in February 2022, about 25,000 people lived in Avdiivka. Despite the shelling, about 2,000 civilians remain, Protsyk said.

For months, authorities have been urging civilians in areas near the fighting to evacuate to safer parts of the country. But while many have heeded the call, others — including families with children — have steadfastly refused.

So it has fallen to police to try to persuade people to leave. A special unit known as the White Angels risk their lives to head into front-line villages and towns, knocking on doors and pleading with the few remaining residents to evacuate.