African diplomats made a push for peace in South Sudan on Friday as bitter fighting spread across the world's youngest nation, with US President Barack Obama warning the oil-rich state was on the brink of civil war. The United Nations Security Council readied emergency consultations on the crisis amid fears that fighting between rival army factions, which has already claimed hundreds of lives and sent tens of thousands seeking UN protection, could escalate. "Recent fighting threatens to plunge South Sudan back into the dark days of its past," Obama said. "South Sudan stands at the precipice." Recalling the promise and hopes that accompanied South Sudan's independence in July 2011, Obama warned "that future is at risk." Over two million people died in the brutal 1983-2005 civil war, which ended in a peace deal that paved the way for the impoverished South's independence two years ago. Bitter power struggles and years of rivalry exacerbated by ethnic divisions erupted into violence late on Sunday, as rival factions within the army loyal to President Salva Kiir or former vice president Riek Machar clashed in the capital Juba. So far close to 500 dead -- most of them civilians -- are reported in Juba alone, but while the capital is now reported to be calm, fighting has continued elsewhere. The UN said incidents of fighting or civil unrest had now been reported from 14 separate areas -- including in the powder-keg eastern state of Jonglei -- and that 34,000 terrified civilians were seeking protection in or around UN bases. UN helicopters flew Friday to rescue staff a day after their compound in the remote Akobo was stormed by attackers, who killed two Indian peacekeepers and wounded one, the UN said, clarifying initial reports all three had died. "Political and personal disputes are escalating into an all-out civil war in which certain ethnic groups are increasingly targeted by the others’ forces," warned Hollywood actor and activist George Clooney and Sudan campaigner John Prendergast. "Billions of petro-dollars... have poured into the country, much of which were used to purchase sophisticated weaponry," they added in an editorial on the Daily Beast. Ethnic killings India's UN envoy Asoke Mukerji said the peacekeepers were "targeted and killed" during Thursday's attack by ethnic Nuer youths on the UN base, which is situated in an area awash with guns and home to several large rebel armies. The fate of more than 30 ethnic Dinka civilians sheltering there is not known. Both the United States and neighbouring Uganda have deployed troops in Juba to protect their citizens, with Kampala saying their forces would also help secure the troubled capital. Emergency flights continue to evacuate foreigners from the troubled country, with the United States and Britain sending in special flights for their citizens, and others fleeing overland south to Uganda. Five regional foreign ministers met with President Kiir in Juba, with Ethiopian Foreign Minister Tedros Adhanom -- leading a team from Djibouti, Kenya, Sudan and Uganda -- saying they had come to "work out a peaceful, amicable solution with all parties". The European Union, Norway and Switzerland said they backed the effort, saying they were "deeply concerned" at "reports of extra-judicial killings on an ethnic basis". Troops loyal to Machar, now a fugitive, seized the town of Bor late Wednesday, as heavy fighting continued in several sites across the vast swamplands and remote bush of Jonglei state. Machar has denied President Kiir's claims he mounted a coup, and has accused the president of trying to cover up a vicious purge. He is now calling for Kiir's ouster, and the conflict has been taking on an ethnic dimension -- with Kiir coming from the majority Dinka people and Machar from the Nuer. UN human rights chief Navi Pillay has also expressed deep concern over reports of "numerous extrajudicial killings", while UN chief Ban Ki-moon said the crisis "urgently needs to be dealt with through political dialogue". Human Rights Watch said witnesses had reported horrific cases of both soldiers and rebels executing people based on their tribe, while Amnesty International described targeted attacks on civilians in an "increasingly vicious conflict". The UN peacekeeping mission said it was sheltering civilians in six state capitals, including Juba and Bor, as well as in Bentiu, the main town of the crucial petroleum-producing state of Unity, where oil workers have been attacked. Oil production accounts for more than 95 percent of South Sudan's fledgling economy, with the campaign group Global Witness warning that "if rebel forces were to capture the oil fields, they could effectively hold the government to ransom."