Cattle can mean everything in South Sudan. They are wealth, status, survival, the price of a bride and the ability to marry and have children – all things young men are willing to kill and die for.
That's what thousands of armed young men from the Murle tribe did last week, pouring across the border on foot into Ethiopia's Gambella region, killing 182 people, including women and children.
They surrounded 13 villages, firing randomly, killing civilians and abducting 108 children. Twenty-six more were killed in Ethiopia last month, bringing the total death toll in the raids to 208, according to Ethiopian officials.
The men were there to steal cattle. They seized 2,000 of the prized long-horned beasts and drove them back across the border.
Poor security in South Sudan's remote eastern region has led to a surge in violence, with a series of cattle-raiding attacks that have left scores of villagers dead, including women and children.
Violence and cattle raiding between the rival Murle and Lou Nuer peoples go back generations in South Sudan, where long-existing tensions over land and water simmer.
The attacks are silent and carefully planned. Huge columns of fighters move on foot across the flat, bushy grassland, taking villagers from rival tribes by surprise, shooting people, slashing them with machetes and burning them in their round thatched huts.
Just a few months after South Sudan gained independence in 2011, bitter fighting broke out between the two groups. Attacks on Murle villagers by Lou Nuer fighters in December 2011 left about 900 dead and hundreds missing and displaced 120,000, according to a report by the peacekeeping
One local official, then-Pibor County Commissioner Joshua Konyi, said 3,000 were killed. The next year, more than 1,000 people were killed in clashes between the two groups.
Convulsions of extreme violence have continued intermittently. The eastern region of South Sudan is so remote that it can take weeks for news of attacks to filter out. Help is far away and villagers tend to flee into the bush to hide, fearing further killings. Helicopter video of past attacks taken by U.N. peacekeepers shows the outlines of burned huts, called tukuls, as far as the eye can see.
In 2013, reports of fighting suggest hundreds or thousands may have been killed. At least 11,000 men were involved in the attacks, according to the government, but casualty figures were never released.
For groups like the Murle and Lou Nuer, cattle are central to life. Tribespeople drink the milk, eat the meat, sleep on the hides, sacrifice bulls at important events and see cows as their only store of wealth. It takes 20 cows to buy a bride, and without a herd, no young man can hope to marry. To some, the fastest way to get cattle is through raiding.
Tension over cattle is common in East Africa, with deadly raids seen in other countries in the region, including northern Kenya.
In past generations, attacks using machetes and sticks were an intrinsic part of reaching manhood and showing valor. Now, after decades of civil war, the region is awash with guns, and young men armed with high-powered weapons from the Murle and the Lou Nuer exact a devastating toll on rival villages.
In the Murle cultural tradition, all cattle belong to the tribe. Militias frequently abduct children during cattle raids, who are then raised as their own. Child abduction is a long and troubling tradition for the Murle people, the roots of which are unclear, though it may be a means to increase the numbers of the small minority group.
The attack in Gambella followed similar, smaller raids in recent months, mainly in South Sudan's Jonglei state. Tit-for-tat violence between the groups in the region has been going on for years, often leading to indiscriminate massacres of civilians.
Escalating attacks late last year left dozens dead, many children abducted and hundreds of cattle stolen. In 2016, militias have stolen hundreds of cattle and abducted more than a dozen children in Jonglei.
On March 29, armed Murle men tried to raid a large herd of cattle, but Lou Nuer herders repelled them. In February, Lou Nuer youths attacked Murle villagers for five days. A local Murle chief, Abraham Mamayo, said many civilians had been killed and thousands of cattle stolen, according to Radio Tamazuj.
In January, 24 people were killed in a cattle raid in South Sudan's Sobat state, two children were abducted and 800 cattle were stolen, according to the Sudan Tribune.
The U.N. peacekeeping force in South Sudan has not been able to protect vulnerable villages in the huge and remote eastern swathe of the country.
Ethiopian communications minister Getachew Reda said Ethiopian forces had killed at least 60 of the perpetrators of Friday's attack. Ethiopian forces pursued the attackers into South Sudan in a bid to free the abducted children.
One factor in the recent upsurge in violence appears to be a long-standing security vacuum in the east.
Authorities have always struggled to prevent ethnic conflict in the region. But the situation appears to have deteriorated after South Sudanese President Salva Kiir removed the Pibor state administrator, David Yauyau, leader of the Cobra militia of Murle fighters; merged Pibor into a new state, named Boma; and appointed a new governor, Baba Medan, who has little influence over the Murle fighters.