According to the Ukrainian minister evacuation buses on the way

According to the Ukrainian minister, evacuation buses on the way to Mariupol are being detained at the Russian checkpoint

A Ukrainian official said Thursday that a convoy of buses en route to the besieged Ukrainian city of Mariupol was stopped at a Russian checkpoint in Vasylivka, a town between the Ukrainian-held city of Zaporizhia and the Russian-held city of Berdyansk.

“Our task is to open a humanitarian corridor and help people survive, especially civilians – women, children, elderly people,” said Iryna Vereshchuk, Ukraine’s minister for the reintegration of temporarily occupied territories.

“As of 12:30 p.m. (5:30 a.m. EST), 45 buses left Zaporizhia for Berdyansk. From this moment they are at the Vasylivka checkpoint, and the Russian Federation again does not let our buses through. Again and again we demand that the entire world community focus its attention and help people get out of occupied Mariupol,” Vereshchuk said.

The International Committee of the Red Cross said Thursday it was preparing to facilitate the safe passage of civilians from Mariupol on Friday.

Vereshchuk said that out of a pre-war population of more than 400,000, about 100,000 people remain in the city and need to be evacuated immediately.

“That means another 100,000 women, children, the elderly and people with disabilities who need our and the world’s help,” she said.

Vereshchuk claimed that 45,000 Ukrainian citizens were forcibly deported to Russia, a figure CNN was unable to immediately verify. The Russian military says thousands have been “evacuated” to Russia from separatist-held regions and “dangerous areas” of Ukraine.

Mariupol Deputy Mayor Sergei Orlov told CNN’s John Berman today that buses are passing through the evacuation corridor.

Orlov said as many as 1,500 to 2,000 people could evacuate the city between today and tomorrow.

He added that there are “constant street battles” in the city, but the Ukrainian army still controls the city center.

The people who remain in Mariupol “live like mice. They live underground in makeshift shelters, air raid shelters. So people are just doing their best to stay alive in this situation,” he said.

According to the Ukrainian minister evacuation buses on the way

CNN’s Adrienne Vogt contributed to this post.