A Cameroonian student has described how he and his friends have been forced to hide in a basement in the southern Ukrainian city of Kherson to escape air raids.

Christophe said that "every five minutes we are hearing bombardments".

"Sometimes we can hear airplanes passing through the sky, mostly bombardments because you can feel it on the ground. That's mostly what we're hearing, they are really not very far from us, they're around the town," he told the BBC's Soraya Ali.

Gun-shots could also be heard.

"We don't know what to do. We are desperate," Christophe said.

"We are either in the basement or in our home. Like one hour in the basement, five minutes at home."

He said that about 15 of them were stranded in Kherson - fellow Cameroonians, Nigerians, Senegalese and Ghanaians.

"The city is said to have been circled by the Russian army. So, there is no way out. We find ourselves in this situation where we cannot do anything," he added.

Their embassies had asked them to reach the border of a neighbouring state, from where they would be picked up, however, it was "impossible" to leave, he said.

"We don't have any way out. Please we are asking for help," Christophe said.