Mbera - It is hardly the most inviting place to call home - a sprawling tent city in a sea of reddish sand in southeastern Mauritania.But for the Malians who eke out a life here, the harsh Saharan desert is a haven compared to the violence and chaos back home.Tens of thousands have fled towns and villages in northern Mali to the safety of Mbera camp, 50km from the border.And for many of them, the craving to go back is offset by the wretched fate of those who have done so.Mohamed Ousmane Ag al-Khalifa arrived in the camp in 2012, fleeing Al-Qaeda-linked jihadist groups that seized key towns in northern Mali, exploiting an uprising by ethnic Tuareg-led rebels.In June 2015, the government and rebels signed a peace accord. Rocket attacks But - as the shepherd and his family were to discover when they ventured back to the Timbuktu region six months later - a deal on paper failed to end violence on the ground."They had told us the peace agreement had been signed at the highest level," said Khalifa, a man in his fifties from the Tuareg tribe of Kel Tagamart, dressed in a black turban and pale green robes."The week after we arrived back, the violence started up," he said. "Our home is on the River Niger, between Goundam and Timbuktu. There were regular rocket attacks on the army, and nomads or their cattle were frequently hit."He eventually scraped up the means to return to Mbera where despite the tough life, there is "peace and freedom"."Our dream of course is to go back, but I know what it's like over there," said Khalifa's wife, Aichetou Walet Mohamed Ousmane, breastfeeding one of their four children.According to UN estimates, around 195 000 people have been displaced by the violence in northern Mali.Around 55 000 have fled to other parts of the country and 140 000 have gone to Burkina Faso, Mauritania and Niger.Mbera itself houses more than 51 000 people, more than two-thirds of whom are from Mali's Tuareg and Arab ethnic groups.The urge to go home is strong.In June last year, Mali, Mauritania and the UN High Commissioner for Refugees (UNHCR) reached an agreement whose provisions include help for individuals to return home voluntarily.By the end of 2016, more than 1 500 had signed up, said the UNHCR's senior official in Mbera, Henri-Sylvain Yakara.One of those who made the return trip was Issa Ag Mohamedoun,who went back home with his family to Haribongo, southeast of Timbuktu. Now they are back in Mbera, where their fifth child was born two months ago.For nearly a year, they lived under the threat of armed groups and thieves. "Robbers tied me and took everything we had," he said. "A short time after that, I scraped together whatever we had and we headed back to Mbera." 'Not for $10 million' The early exodus from the camp has dried up, with only a few hundred leaving so far this year, and has been counterbalanced by a flood of arrivals. Since September 2016, a wave of displaced people has come in from Timbuktu, Goundam, Mopti and Nampala.The camp is struggling with a shrinking budget, which has prompted a reduction in food rations and "malnutrition problems for some children", Yakara said.But when it comes to deciding between a rumbling stomach or heart-wrenching terror, Mohamedoun said there was only outcome."I wouldn't go back to Mali even if you gave me $10 million," he said. "Life is more important than that."