( CNN ) -- Gunmen launched grenades and used machetes against Muslims being evacuated in a truck convoy in Central African Republic , killing at least three children and 19 adults , a humanitarian group said Saturday . At least 23 more people , including children , were injured in Friday 's attack and were being treated in a hospital in Bouar , in the northwestern part of the country , said Michael McCusker with Save the Children in Bangui , the nation 's capital . The African country has been wracked with such serious religious and ethnic violence , including between Muslims and Christians , that the United Nations has said it fears a genocide could be brewing , and aid groups warn of a humanitarian crisis . The convoy was carrying mostly Muslim families from the village of Vakap when a grenade was launched into the trucks , said officials with Save the Children , a U.K.-based aid group . Attackers hacked many victims with machetes , the group said . Nearly a million flee violence . The mostly Muslim families in the convoy were being evacuated from violence and were ultimately destined for refuge in neighboring Cameroon . `` It is a sign of the still fraught and highly dangerous situation in the Central African Republic that children and their families have been attacked and killed while trying to evacuate to safety , '' said Robert Lankenau , the group 's director in the country . The Bouar hospital treats both Christians and Muslims , the group said . Security has deteriorated since the country 's interim leaders , President Michel Djotodia and Prime Minister Nicolas Tiangaye , announced their resignation at a regional summit in Chad this month . Chaos struck the Central African Republic last year after a coalition of rebels dubbed Seleka ousted President Francois Bozize , the latest in a series of coups since its independence . Rebels infiltrated the capital in March , sending Bozize fleeing to Cameroon . Djotodia , one of the Seleka leaders , then became interim president in a coup . Since then , political turmoil and violence has spread . Seleka is a predominantly Muslim coalition . To counter the attacks on their communities , Christians assembled vigilante groups and fought back . The violence prompted U.N. fears about a genocide brewing . Children beheaded as violence grows . At least 1,000 people have died in the violence , and some 958,000 more people , many of them children , have been forced from their homes within the Central African Republic , according to the United Nations ' refugee agency , UNHCR . There are also more than 86,000 refugees in Cameroon , Chad , the Democratic Republic of the Congo and the Republic of the Congo who fled the Central African Republic in 2013 , the UNHCR said Friday . Some 100,000 people have gathered at a makeshift camp by the international airport in Bangui , seeking refuge from the violence . French troops have deployed under a U.N. mandate to assist African peacekeepers . Sick and desperate , migrants wait for airlift home .
`` It is a sign of the still fraught and highly dangerous situation , '' aid leader says . The United Nations has warned that more than half of Yemen's population faces starvation as fighting between government forces loyal to President Abd-Rabbu Mansour Hadi and Houthi rebels rages in Sanaa. The African country is wracked by violence between Christians and Muslims . At least 23 more people are injured and being treated at a hospital the group supports .