Isolated from the world by President Isaias Afwerki’s 30-year authoritarian rule, the east African nation of Eritrea remains intentionally unknown.

“It’s impossible, or very difficult, to get an accurate picture, because the government has closed the country so effectively that even those who have successfully fled the country are afraid to speak publicly, out of fear for what could happen to their families,” said Adotei Akwei, an Amnesty International deputy director who specializes in sub-Saharan Africa.

In the new FRONTLINE documentary Escaping Eritrea, filmmaker Evan Williams explores the human rights landscape of one of the world’s most repressive regimes, from compulsory conscription to the ongoing exodus of refugees. The Eritrean government declined to respond to FRONTLINE, other than to say they’d seen many fabricated stories before. Here is an introduction to five of Eritrea’s biggest human rights crises.