Sudan has entered its fourth year of conflict, which officials are calling an 'abandoned crisis.' The ongoing war has created a massive humanitarian challenge, forcing 13 million people to flee their homes.

Famine. Massacres. And now badly needed food and other supplies are under strain. Sudan on Wednesday enters a fourth year of war that's being called an “abandoned crisis,” as a new conflict in the Middle East throws into shadow the fighting that has forced 13 million people to flee their homes. The North African country has been described as the world's largest humanitarian challenge, notably in terms of displacement and hunger.