Some half a million residents of the capital, Mark Kelly, have been warned to stay indoors.

The move comes just hours after an ultimatum expired for regional leaders to surrender to the central government.

The U.

N is warning it's running low on essential supplies for the nearly one million people who have been displaced by the conflict.

Our correspondent Mariel Mueller reports.

We're only 80 kilometers away from the Ethiopian border into the region of Tigray, where heavy fighting still continues.

This U N camp, called Umrah Cuba camp, once housed refugees who fled Ethiopia's famine in the 19 eighties.

Now the camp is expected to house several 1000 refugees.

As the U.

N refugee agency told us.

Many more than the original capacity of 6000 people here are desperate, they tell us water, food and shelter are scarce.

Some of them have to sleep on the ground, are struggling to get enough food or medical aid.

The new refugees crossing the border to Sudan worry aid groups, a representative told us, were unable to respond to a growing influx.

Umbra Cuba Camp once housed refugees who fled Ethiopia's famine in the 19 eighties.

Now some 9000 people have saved themselves once again, but this time it's because of war.

In this hospital, people wait for hours before receiving treatment like a gorilla.

She, her baby and her father escaped the war in the degree in town off.

Um, era E was afraid because the bombs kept falling for three days.

We just left without money without close.

It took 10 days to come here and now we're here in Sudan.

We've been in this camp for three days.

We don't have any shelter.

Well again, mind you, Her father has terminal cancer.

Since they got out, he hasn't received his medication.

Yeah, the U.

N refugee agency is bracing for more refugees crossing the border from Ethiopia.

People need everything from water, food and shelter.

So at the moment we're capturing for over 9000 people at the hot meal to your partner, and that's not enough.

And it's Children who are suffering the most.

It's estimated that half off the refugees are Children.

Many of them need medical treatment.

Like five month old Collab.

He's been coughing and has had diarrhea since days.

Exactly.

I can't breastfeed him.

And here they don't have milk powder And the food the baby needs.

Outside the hospital, we meet Alum whose house was bombed.

In whom era?

The side of reportedly some of the heaviest fighting between Ethiopian forces and the Tigre.

An army.

He got shot in the leg.

I'm alone.

My mom and my dad were killed by the bombing.

These clothes are my only ones.

I wear them for days.

Nobody helps me.

I don't have enough water or food here.

Nobody takes care of me.

E If more refugees arrive, Alum fears that the situation could get even worse.