Over the past month, the number of testimonies has increased.

Ukrainians fleeing areas controlled by the Russian military are stopped along the way and interrogated in search of views considered "too Ukrainian".  

- Luckily we were warned and had time to clean our phones.

They went through messages, photos and social media.

They were looking for Ukrainian symbols and tattoos, says Andryi Shapranov when we meet him in the Dnipro in Ukraine.

Andryi escaped the devastation in Mariupol by bicycle with two friends on April 11 this year.

In Mangush, they were stopped by the Russian military.

The filtration took three days.

Andryi says they were lucky to get through.  

- I saw that some people who were in the queue who did not return from the interrogations. 

Organization: End up in jail

Belkis Wille from Human Rights Watch documents suspected war crimes in Ukraine. 

- We hear that people who are not let through the filtration end up in prison in Donetsk.

Some of those who flee are also taken to Russia, she says.  

Both the governments of Russia and Ukraine state that hundreds of thousands of people were bussed to Russia from Ukraine during the war.

Belkis Wille emphasizes that some wanted to go to Russia, while others were taken there against their will.

"Many do not show up"

One of those taken to Russia is history teacher Vytaly Lytvynenko, who wanted to go to Ukraine.

On May 23 this year, he tried to leave Mariupol.

Together with his neighbors, he took one of the buses that left the city. 

- The buses were the only way out.

I have heard that those who have a car can drive towards Ukrainian territory but many do not arrive. 

- We were taken to a vast field that was surrounded by barbed wire.

Women and men were placed in different ranks.

We were forced to go into large tents and undress naked.

It was a sight that did not belong in the twentieth century. 

Vytalij passed the filtration and was taken by bus to Russia.

He later managed to get to Estonia.

The neighboring family he fled with did not move on.  

- Now they are still in Russia, he says.