The humanitarian situation in violence-hit Central African Republic is deteriorating at an "alarming rate", the UN said on Wednesday, warning that famine would hit if nothing is done to reverse the trend.Growing unrest in the country of 4.5 million people is forcing many to flee their homes and abandon their fields, causing spiralling food insecurity, United Nations humanitarian coordinator in the country, Najat Rochdi, told reporters in Geneva.If the situation remains the same, and people do not return to their fields, ... "it means that yes, in very few years we will have a famine in Central African Republic," she said."We are not talking about 10 people. We are talking about hundreds of thousands" at risk, she said, pointing out that several regions have already reached level 4 in terms of food insecurity - just away from famine.Thousands have been killed and a quarter of the population has fled during violence triggered after President Francois Bozize, a Christian, was overthrown in 2013 by mainly Muslim Seleka rebels, triggering Christian militia revenge attacks.The UN's World Food Programme warned earlier this month that CAR was facing the worst situation of food insecurity in four years, with nearly two million people in urgent need of food aid.Fresh data from the UN humanitarian agency, OCHA, meanwhile showed Wednesday that 2.9 million people - 63% of the population - require aid and protection."The world cannot turn a blind eye to what is happening in the CAR. We are back to square one," Rochdi said, deploring "despicable attacks" which are "taking a huge toll on the lives of innocent men, women, boys and girls."In the past three weeks alone, more than 50 000 people have been impacted by violence in the northern town of Batangafo and in the central town of Alindao.Two sites hosting displaced people in those areas were also torched, OCHA said."As humanitarians, we continue to scale up emergency response assistance, but in these two towns we have to do it from scratch as our achievements have been lost," Rochdi said.One of the world's poorest nations despite a rich supply of diamonds and uranium, the CAR has struggled to recover from the 2013 civil war that erupted when Bozize was ousted. In response, Christians, who account for about 80% of the population, organised vigilante units dubbed "anti-Balaka" in reference to a local machete. Rochdi called for a halt to the violence and for the government, armed groups and the international community to help avoid a "catastrophic scenario"."I am raising the alarm not to say famine will arrive tomorrow, but to say that every possible measure must be taken to ensure that it doesn't," she said.* Sign up to News24's top Africa news in your inbox: SUBSCRIBE TO THE HELLO AFRICA NEWSLETTERFOLLOW News24 Africa on Twitter and Facebook.