Some 4,000 Eritreans flee their country each month because of government repression and military conscription, according to a UN investigator. Many arrived in Italy as boat refugees.
UN special rapporteur Sheila Keetharuth said on Thursday that Eritrea's system of forcing all citizens from the age of 18 into military service equated to "forced labor" and was resulting in a "shocking" exodus, especially of young people.
She said many risked dangerous journeys across deserts and seas - some toward Ethiopia and Sudan - rather that toil for Eritrea's military or other government jobs for hardly any pay - even until retirement age.
"People know those risks - they take them because there are no other choices," Keetharuth said in Geneva. "If this trend continues, Eritrea will soon be a country without people inside."
She also accused the government of President Issaias Afeworki of arbitrarily detaining Eritreans and punishing them with impunity in secret detention centers.
Eritreans among boat refugees
Since January alone, some 13,000 Eritreans had arrived by boat in Italy - accounting for a third of all arrivals, according to the UN's refugee agency.
That compares with 9,800 for the whole of 2013.
Alone in April, more than 3,000 Eritreans applied for asylum in European countries, Keetharuth said.
Next week, the UN Human Rights Council is due to consider a resolution calling for the appointment of a special of three investigators, including Keetharuth, to probe the situation inside Eritrea.
Keetharuth has not been allowed into Eritrea but said she had spoken with some of the thousands of Eritreans who had fled.
- AP, AFP