Her younger brother had just left to sit his GCSE English exam when the sound of rapid gunfire began to ring out on their residential street.

"It was so hectic. Everything was just panic, panic, panic," she said.

Within hours, Sarah's neighbourhood became the centre of a power struggle that had erupted into warfare.

Soldiers from the paramilitary Rapid Support Forces (RSF) took up station along their road and from then on, the fighting was relentless.

"There was nothing we could do. There was fighting the whole day," she said. "We couldn't even sleep."

At first, it was gunfire. But by the second day, the Sudanese Army began targeting the area with air strikes.

"It was horrible. Every time they fired something our whole house would shake," she said.

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The family was forced to hide as the conflict raged just metres from their home. By last Wednesday, it had reached their doorstep.

"A shell landed on the school opposite and then an hour later, one fell into our home. So we had to leave, we had to evacuate," Sarah added.

"All the windows were broken, the front door had melted. Even the electric wires outside were torn apart."

Fortunately, Sarah's family were largely unharmed aside from a shrapnel injury in her uncle's leg.

But it had become too dangerous for them to stay at home, so they braved the treacherous journey through the chaos to another relatives' house nearby.

"It was so scary, I was driving on the road and RSF forces were passing right by me," she said.

It was there the family decided to leave Khartoum altogether for Cairo in Egypt - a journey that would end up taking them 66 hours.

Sarah's family is one of thousands that have decided to escape Khartoum and other battlegrounds following over a week of intense violence which has seen over 450 killed, according to the United Nations.

Historically, Khartoum has been spared the violence afflicting other parts of the country.

But for the past week, Sudan's capital has been the epicentre of the battle between de facto President al-Burhan's armed forces and his rival Mohammed Hamdan Dagalo's RSF.

The city's residents are now leaving in droves, headed by road for areas both inside Sudan and abroad where they hope to find safety.

The United Nations has said 20,000 refugees from Sudan have crossed into neighbouring Chad, while 4,000 South Sudanese people living in the country have returned home following the conflict.

Others have headed east on the 35-hour journey towards Port Sudan on the Red Sea, where ships leave for the Saudi Arabian coastal city of Jeddah.

After the shell hit, Sarah's family chartered a bus to take them to the border with Egypt around 570 miles away.

She says they paid the equivalent of around £170 per person but prices are increasing daily - and providers are now charging well over double that.

The fighting had moved north of the Nile River which allowed them to leave in a period of relative calm. The group had to pass through several RSF and Sudanese Army checkpoints as they left, but she says the soldiers let them through without trouble.

First, they went to Dongola where they spent the night, before carrying on to the Egyptian border at Argeen.

"We spent 20 hours on the border. It was so crowded, everyone was there," she told Sky News.

"People were outside just laying on the ground because the buses were so uncomfortable," she said.

Egyptian state TV said on Tuesday that more than 100 buses carrying Sudanese, Egyptian and other nationalities had arrived in the last few hours alone.

The chaotic situation on the Egyptian border has meant that some people are considering other routes.

After spending five days hiding alone at his home in Khartoum amid the violence, Marwan had hoped to join the masses heading for Egypt.

But when his neighbours informed him they were travelling to nearby Al-Jazira state, he decided to join them.

"I didn't want to leave. I was scared because I was alone. They [the warring sides] are good with families, but me being on my own…it was very scary," he said.

The group decided it was safest for some of the other members to join Marwan in his car for the journey, so as not to arouse suspicion at checkpoints.

Marwan says that he was questioned by RSF soldiers about the U.S. dollars he was carrying at the checkpoint.

"They were saying: 'You're going away with dollars!' and things like that, but they were just playing with me I think," he said.

After the convoy was let through, Marwan says paramilitaries fired shells on the side of the road.

"I guess they wanted to scare us…or they were trying to be funny," he said.

"The thing is, Rapid Support Forces are mainly kids. A lot of them are around 16-years-old."

After around four hours, he arrived in the town of Al-Hasaheisa where he met his extended family who had arrived the day before.

Marwan says that some of his relatives are still trying to get their passports, which had been left at an office in Khartoum that has been dangerous to visit in recent days. But as soon as they receive them, they plan to go abroad.

"We wanted to go to Egypt, but the situation at the border is so bad. I spoke to my friend who is there - people are staying there for full days. Mosquitos everywhere, no food, no bathrooms," he said.

He hopes to travel to Addis Ababa in Ethiopia, from where he will travel onwards to join his family in Dubai.

Since Sarah and Marwan left their homes, the two warring sides have agreed to a 72-hour ceasefire brokered by the United States and Saudi Arabia.

Thousands are hoping to use the opportunity to evacuate, including foreign governments which are in the process of repatriating their citizens using airfields near the capital city.

But the situation remains unstable, with reports of battles raging in Darfur and near Khartoum.

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