The number of people entering Ukraine from neighboring Poland has exceeded the number of people crossing the border in the other direction, as the changing war situation prompts more people who evacuated to return.

The United Nations has said that as of May 13, 3.31 million people, or more than half of those who fled Ukraine, crossed into neighboring Poland since Russia's invasion began in February.

Poland's border security authorities said about 135,000 people crossed into Ukraine from Poland between last Tuesday through Saturday, while about 105,000 people entered Poland from Ukraine.

Experts say more people started returning to Ukraine after Russian forces withdrew from the capital Kyiv in late March.

People returning to Ukraine lined up at a customs checkpoint in Poland's southeastern border city of Medyka on Saturday.

A 36-year-old woman who was returning to her home in Lviv in western Ukraine with her 10-year-old daughter said she evacuated to her friend's house in Poland after the airport near her house was bombed, but she thinks things have settled down now.

An NHK crew filmed about 100 men, led by some wearing US Army uniforms, heading to the border in Medyka on Saturday.

When a crew member asked one of them if they were going to Ukraine to fight, he said yes.

US media quote sources as saying the US military is giving weapons training to Ukrainian soldiers in Poland.

NHK asked the US Army to comment on this, but has not heard back.