ZAGREB, Croatia (AP) — Doctors are treating small children for exposure as dropping temperatures worsen the plight of asylum-seekers walking for days in hopes of reaching sanctuary in Europe.

A new group of migrants crossed into Croatia late Sunday, crossing the border near the small village of Bapska. They walked through cornfields and forests to pass through a small gate that marks the border between Croatia and Serbia.

Vladimir Bozic, a physician from Doctors without Borders, says he treats many very young children.

"We saw a 1-month old baby, even 15 days," Bozic said.

Volunteers from the U.H. High Commissioner from Refugees handed out blankets, warm drinks and food to the people, who are fleeing conflict and poverty in the Middle East, Africa and Asia.