By James Copnall
BBC News, eastern Sudan
"I realise there are political problems everywhere, but in Eritrea it is unique," says Habtu Zere Maram, one of a thickening flow of Eritrean refugees who have crossed the border into Sudan.
Many children flee Eritrea without their parents
"It's like the Middle Ages. Now we are in the 21st Century, how can we live like this? You can't speak, there is no freedom, you cannot say whatever you want to say.
"I dreamt of leaving, because I want to live free. Most of the Eritrean people think the same thing."
Last week, a group of Eritrean footballers absconded in Kenya, where they had gone to play a football tournament.
Eritrea has a population of about 3.5 million but more than 1,800 refugees - almost all Eritreans - cross the border into eastern Sudan every month, according to the UN's refugee agency, the UNHCR.
Many of the refugees end up in tents in places like the Shagarab camp, where living conditions are difficult.
But the UNHCR says some refugees - usually political opponents of the Eritrean government - are too scared to live in the camps, as many people fear the Eritrean state has spies there.
A previous generation of Eritrean refugees still lives in camps in eastern Sudan, and some have been there for four decades.
The UNHCR estimates there are currently more than 66,000 in the camps, and maybe another 40,000 in urban areas.
Most of the long-term refugees came to escape hunger in Ethiopia or the conflict between Eritrea and Ethiopia and have never returned home.
But the new arrivals do not want to be caught in the same situation and hope to move on quickly.
Mohamed, a 13-year-old, speaks for many when he says his objective is to make it to Europe.
His few words of English delight the gathered crowd.
Like many of the children in the camps, Mohamed crossed the border without his parents.
No money, no prospects
Another topic of conversation that has everyone nodding in agreement at the Shagarab camp is the hated Eritrean national service.
There is fear among the camp's residents that Eritrea may have spies there
"Military service was terrible. I could say pages and pages and pages about it," Mr Habtu says.
"You don't have enough to eat. I am a young person, I must eat a lot. How can you serve there? Even if you have a desire to live in Eritrea... well actually, you can't desire to live there."
Mr Habtu's case is far from unique.
Ura, a teacher, says he also left Eritrea because of national service.
He was not forced to join the army - instead he served as a teacher.
But the pay was poor and he says future prospects were limited.
"National service continues until you get to 40 years old. There is no good salary, and the service continues, it doesn't stop. It's difficult to live like that," he says.
UN figures 'untrue'
Another educated man, who asked not to be named, says he smuggled his whole family out because he was worried about his children's future.
He says he was paid just a few dollars a month in Eritrea, despite being well qualified.
Some refugees have been in Sudan for years
Despite these complaints, the Eritrean government categorically denies that so many their people are fleeing and calls UN figures "untrue".
In a BBC interview last month, Information Minister Ali Abdu accused the UNHCR of being "involved in human trafficking" and said some UN workers were "intelligence agents".
He said many asylum seekers often pretended to be Eritrean because "Western countries and MI5" gave priority to Eritreans to encourage them to flee.
All the same, the fear in the camp is certainly real.
Some refugees said they were too scared to speak, or hinted that they were being watched.
In careful handwriting, one refugee wrote out his complaints about the poor conditions in the camp on a piece of paper.
More than 20 families are housed in one large, fairly ramshackle tent, with little privacy and not enough bedding.
"To live here is difficult, really it is difficult," says Mr Habtu.
"Us young people, we have to put our hands out to beg. I hate that. We don't have enough blankets, we don't have enough mattresses.
"We don't have enough food either. But at least this place is better than Eritrea. At least I will survive."