Eritrea is "adding to the global refugee crisis" with a policy of indefinite national forced conscription that drives people to flee the Red Sea country, Amnesty International said in a report.

Eritrea has said conscription would be limited to 18 months, but in practice it amounts to forced labor that can often last for decades, the rights group said after interviewing more than 70 Eritreans who fled the country.

"Conscription continues to be indefinite for a high proportion of conscripts and sometimes lasts for decades. Older people are re-conscripted, and those who try to escape are arbitrarily detained without charge," said Michelle Kagari, Amnesty International's Deputy Regional Director for East Africa, the Horn and the Great Lakes.

Eritrea claims it must implement forced conscription to defend itself against Ethiopia, with which it fought a 30 year war for independence. Hostilities continue and Ethiopia occupies some Eritrean territory.

But in many instances conscripts are forced to do farming, construction, teaching and other civilian positions, while only making roughly $45 (50 euros) a month, Amnesty found.

Conscription affects the young, old, women, men and families, destroying the prospect for Eritreans to have any say in determining their future, Amnesty said.

Pay is "abysmal," leave is not granted, and families are torn apart.

Eritrea's information minister Yemane Meskel responded on Twitter that Amnesty had no authority to address defense issues and slammed Ethiopian occupation.

Fleeing to Europe

Forced conscription and human rights abuses are pushing tens of thousands to make the dangerous trip to Europe.

However, some countries are increasingly turning back Eritreans, claiming they are economic migrants to be deported, unlike Syrians who are escaping war.

Along the Macedonia-Greek border over the past two weeks authorities have prevented economic migrants from moving on to Europe, allowing only refugees from war-torn countries like Syria and Iraq.

The fact that so many Eritreans are braving the dangerous trip to Europe reflects the "gravity of the human rights violations they would face if they stayed at home,” Amnesty said.

Some countries in Europe have claimed the situation in Eritrea has improved to the point where refugees should not receive asylum, a policy that Amnesty said was endangering thousands of lives.

"The situation facing conscripts in Eritrea is desperate and exposes the lie behind claims made by certain host countries that most Eritreans arriving at their borders are economic migrants," Kagari said.

People caught fleeing the country or avoiding military service are often detained for long-periods in inhumane conditions, according to the report. In some cases deserters are held in underground cells or shipping containers.

"The same fate would likely befall those forcibly returned from overseas upon the rejection of their asylum applications in Europe or elsewhere, and there is a generalized risk of arbitrary detention and torture and other ill-treatment for any returned asylum-seekers," the report said.