A Ukrainian military commander said on Tuesday that the civilians and soldiers hiding from Russian troops in Mariupol may only have hours or days left to live.

Maj. Serhii Volyna, commander of the 36th Separate Marine brigade, spoke to CNN and urged other countries to help evacuate people from the plant.

I have something to say to the world. We have only a few days left, so it may be my last statement.

We appeal to world leaders to apply the procedure to the military of the Mariupol garrison, to the civilians who are with us here at the plant. We want you to take us to the territory of a third country and give us security.

He said there were hundreds of civilians in the plant, and that around 500 military members were injured. The Russian presence in the city made it difficult for them to get medical care.

The Azovstal Iron and Steel Works plant, which has a network of underground tunnels, has been home to Ukrainian civilians and troops for several weeks. The Associated Press reported that Russia has started dropping bombs on the plant that are designed to target underground and well-fortified areas.

The City Council of Mariupol said on Telegram on Monday that most of the civilians in the plant were women with children and elderly.

Children were among the civilians at the plant, according to the head of the patrol police.

The steel plant is a shelter for troops and civilians in the city, and it may be the last place of resistance there.

A Mariupol police official told CNN that there was a shortage of food and water.

Mariupol, a port city which would give Russian forces a significant strategic advantage if completely captured, has been one of the worst-hit areas since Russian troops invaded the country. Russia would have control over the land route from the eastern region of the country to the peninsula.

Ukrainian soldiers have refused to surrender despite repeated orders from Russia.

Ukrainian officials estimate that over 20,000 people have been killed in the city. The death toll in Mariupol is unknown, according to the governor.

The city doesn't exist anymore according to Ukrainian Foreign Minister Dmytro Kuleba. The Russian forces encircled the Ukrainian army and a large group of civilians.