AWEIL, South Sudan—More than one million refugees have fled South Sudan’s ongoing civil war, overwhelming aid agencies and creating one of the world’s worst humanitarian disasters.
The United Nations said Friday that South Sudan joins Syria, Afghanistan and Somalia as countries that have produced over one million refugees.
“This is a very sad milestone,” said Leo Dobbs, a spokesman for the U.N. refugee agency. South Sudan’s estimated population was over 12 million last year, according to the World Bank.

Refugees who fled the recent violence in South Sudan and crossed the border into Uganda arrive and await transportation from a transit center in the town of Koboko, Uganda, on Jan. 6 2014. AP Photo/Rebecca Vassie