A familiar foe has ramped up its activities in central Africa. Raids by the notorious Lord's Resistance Army (LRA) are becoming more frequent and, as the BBC's Peter Martell reports, a sense of alarm is spreading.
Stephen Taban spent two years fighting for the LRA. The 20-year-old does not need time to think about which parts were the worst.
"Killing people and catching the kids," he says, looking down at the ground as he speaks.
"It was a bad time. We were told: 'Go and bring back the small children.'"
He knows what terror that caused: he was conscripted after being snatched from his family's farm in southern Sudan.
But if the jungle rebels failed to return with food and fresh recruits, commanders would burn them on the back with red-hot metal from a fire.
"I was a soldier, I was carrying a gun," he says.
"I didn't like it, but I was forced to fight."
The fighters - whose leaders originate in northern Uganda - have earned a grim reputation for murder, rape and abducting children.
Mutilating victims, including hacking off noses and lips, is one of their trademark calling cards.
Boys are taken to become fighters, girls as sex slaves for the commanders.
Mr Taban escaped in June, running away through the thick forests and swamps that the guerrillas hide in.
He still wears the green T-shirt with a Ugandan army logo given to him after he surrendered.
Ironically, it was the Ugandan army that the LRA leadership began fighting two decades ago - although the rebels have long since shifted northwards.
Moving in small groups, the machete-wielding rebels now menace a wide region across southern Sudan, the Democratic Republic of the Congo and the Central African Republic, dragging in recruits from several nations.
While the war is over for Mr Taban, the rebel raids increase.
Aid agencies targeted
The UN humanitarian co-ordinator for Sudan, Ameerah Haq, said there was "grave concern" at "escalating attacks".
The rebels have waged war in several countries
"Many innocent people are losing their lives every week," she says, speaking during a visit to Yambio, capital of the hard-hit Western Equatoria state.
Rebels raided just three miles outside Yambio earlier this month, while aid workers had to be airlifted by helicopter out of the remote town of Ezo after attacks in August, shutting down international aid efforts there.
"The United Nations is very concerned about the killing, abduction, maiming and displacement of innocent civilians," Ms Haq said.
Many of the attacks targeted the food provided by international aid agencies, she said, warning that greater security efforts were needed.
There are just 200 UN peacekeepers in Western Equatoria, with forces already stretched tackling separate conflicts elsewhere in southern Sudan.
Some of the 68,000 civilians who have fled their homes this year from rebel attacks in the remote southern Sudanese state have come to Yambio for safety.
At least 188 people from southern Sudan have been killed and more than 130 abducted since December.
Many in the camps see no prospect of a return home
"They attack normally at night, but they also like to come on a Sunday, because they know we will all be together at church," said Veronica Cosmos, who fled Ezo in August with her small baby after rebels snatched her other child.
"We don't have much shelter or food here, but we are not safe in Ezo."
The rebels have also attacked Congo - killing at least 1,270 people, abducting 655 children and forcing some 540,000 people to flee in the past 12 months, according to the UN refugee agency.
"We cannot go home, but life in the camp is hard," said Gaaniko Bate, at the ever-growing Makpandu camp in southern Sudan, where more than 2,500 Congolese refugees are building new homes of plastic sheeting and thatch huts.
"How long will we have to wait? We cannot protect ourselves at home against these people."
Source: BBC News Africa