By Katy Migiro

JUBA, Feb 13 (Thomson Reuters Foundation) - In South Sudan's capital, Mary Nyapini Malual watches her children jostle over a plate of stew and pancakes, grateful they are safe from a government she believes wants to kill them.

It has been more than a year since Malual ran from clashes that broke out after months of tension sparked by President Salva Kiir's decision to fire former vice president Riek Machar.

Since then tens of thousands of people have been killed and over two million forced from their homes in the violence.

As fighters from Kiir's dominant Dinka ethnic group went door to door searching for members of Machar's Nuer in December 2013, Malual fled to the only sanctuary she could think of - a U.N. military base on the edge of Juba.

She now lives alongside thousands of other Nuer in the government-controlled city who are too fearful to go home, citing continued insecurity despite a series of ceasefire deals between the warring parties and often faltering peace talks.

"If Salva Kiir is still the president, I can never go back home," Malual said. "The president knows we are Nuer and if these children come out, he will kill them."

Abuses by both sides have been reported during their offensives to capture key towns.

Aid workers say the same fear of reprisal attacks has been expressed by other ethnic groups, such as Dinka and Shilluk, who fled to the U.N. Mission in South Sudan (UNMISS) base in Malakal when the northeastern town was seized by rebels last year.

However, the government says there is nothing to worry about and is keen that the 113,000 people who have taken refuge in six U.N. military bases across the country should go home.

"We do not need protection sites," presidential spokesman Ateny Wek Ateny told the Thomson Reuters Foundation.

"They should come out and go back to where they were before ... There is no reason why a certain tribe should see itself as a target because government doesn't target any tribe."

ANGER, PARANOIA

Juba, where some 35,000 mostly Nuer are squeezed into UNMISS camps on its outskirts, no longer feels like a city at war, despite numerous military uniforms on the streets.

Rooftop bars buzz with music after a year-long curfew was lifted in December. Visitors pose for photos in an open-air restaurant by the Nile as a jazz band plays Louis Armstrong hits.

But most of the internally displaced (IDPs) are too scared to venture out beyond their U.N. base with its barbed wire and green earth-filled plastic bags.

"If you go out, who will protect you?" said Hoth Gor Luak, the IDP chairman of one of the camps.

Rights groups say the security forces harass IDPs when they leave the camps and many of their homes have been burnt, looted or occupied.

Life in the slum-like camp, where foul-smelling open drains flow past people's front doors, is not easy. Tensions regularly spill over into violence.

Aid agencies stopped delivering food to the Juba camps for several months after their staff were attacked by IDPs who insisted on being fed with sorghum imported from the United States, rather than from local Juba traders.

"We don't trust those traders," said Luak. "Most of them are Dinkas ... They can poison it."

U.N. police have also been attacked by IDPs with machetes and spears while trying to break up fights between them. UNMISS has recovered hundreds of weapons, including pistols, AK-47s and iron bars, from the IDPs in the camps.

"A huge number of people are forced to live in small areas together, in mixed communities, and are agitated," said Natalie Smith, a psychologist working with Handicap International in the Juba camps. "Frustration leads to anger. It leads to conflict."

Journalists have been stoned and accused of being government spies. "There is a lot of suspicion, there is a lot of paranoia," Smith said.

Many camp residents witnessed their family members being killed during the conflict, and often use opium and alcohol to blot out the pain, Smith said.

U.N. PEACEKEEPERS

UNMISS is caught in the middle between the government, which wants the IDPs to go home, and aid agencies who believe it is too early to talk about returns while the conflict continues.

On Tuesday, barely a week after another ceasefire deal was signed, there was shelling in Bentiu and Upper Nile states.

Most of the 10,000 UNMISS peacekeepers in South Sudan are dedicated to protecting UNMISS camps housing IDPs, UNMISS spokeswoman Ariane Quentier said. Yet most of the country's 1.4 million IDPs live outside the camps.

At the United Nations General Assembly in September, Kiir chastised UNMISS for focusing too much on protecting civilians and not enough on state-building. He also said UNMISS needed to protect civilians in their neighbourhoods and not in camps.

In an attempt to create the conditions for IDPs to be able to return, UNMISS is helping to finance a police project in the capital aimed at boosting citizens' confidence in the force.

Police posts are being built in parts of Juba where the IDPs came from and 400 officers are being brought in from non-conflict regions.

More than 170,000 IDPs have returned home nationwide since the crisis began, but thousands continue to arrive at UNMISS sites in active conflict areas, like Bentiu, U.N. officials say.

"They want to get home as quickly as possible and they are waiting for peace. Not only a message from a politician, but a real sense that they can go home and make it through the night safely," said the U.N. humanitarian coordinator for South Sudan, Toby Lanzer.

(Reporting by Katy Migiro; Editing by Katie Nguyen)