Sudan's hidden war in 15 Hipstamatic photos

A woman and her child from the Nuba Mountains in Sudan wait outside of a refugee camp registration center in Yida, South Sudan, on April 25, 2012. After an initial attack by rebel forces in South Kordofan, thousands of people from the Nuba Mountains have fled to neighboring Yida to escape the fighting and retaliatory airstrikes by the Sudan Armed Forces.

Mostly black African rebels with a mixture of Christian and traditional beliefs have fought a long series of civil wars with the Arab Islamic regimes based in the Sudanese capital, Khartoum. The International Criminal Court charged the Sudanese president with war crimes and crimes against humanity for his crackdown in west Darfur in 2008.

But the conflict here kicked off again in 2011, displacing hundreds of thousands and interrupting already meager health and education services.

A dust storm whips through Yida camp in South Sudan, home to more than 70,000 refugees who have fled the war in the Nuba Mountains of Sudan. Tristan McConnell. Instagram.

A crashed cargo plane next to the airstrip at the Yida refugee camp in South Sudan has become a makeshift children's playground. Tristan McConnell. Instagram.

In Sudan's Nuba Mountains, a destroyed government tank, remnant of a battle last year against SPLA-North rebels. Tristan McConnell. Instagram.

Civilians walk along a dirt road in the Nuba Mountains region of Sudan. Tristan McConnell. Instagram.

A Nuba lunch of okra and bean stew, grilled goat, fried liver and bread on a shared plate in a roadside shack in Sudan. Tristan McConnell. Instagram.

Corridors have become wards at the only hospital in rebel-held Nuba Mountains, where Dr Tom Catena and his team do incredible work keeping people alive. Tristan McConnell. Instagram.

Life goes on despite the conflict: kids play volleyball after school in the Nuba Mountains. Tristan McConnell. Instagram.

A child stands outside his house on a hilltop in the Nuba Mountains as the sun sets one evening. Tristan McConnell. Instagram.

A man rebuilds a drystone wall ahead of the rainy season at his home on a hilltop in Sudan's Nuba Mountains. Tristan McConnell. Instagram.

Sunset over the Nuba Mountains in Sudan. Tristan McConnell. Instagram.

Remnants of a battle between rebel and government troops in Sudan's Nuba mountains. The hidden war there is into its third year. Tristan McConnell. Instagram.

A rebel commander in Sudan's Nuba mountains points toward the frontline a few miles away. Tristan McConnell. Instagram.

Woman stands in the doorway of her traditional home on a hilltop in Sudan's Nuba mountains. Tristan McConnell. Instagram.

Refugee children from Sudan's Nuba mountains clamber over the carcass of a crash cargo plane at Yida in South Sudan. Tristan McConnell. Instagram.