Juba, South Sudan (CNN) -- East African leaders on Friday gave South Sudan's warring factions four days to lay down their arms after nearly two weeks of widening violence. If they don't, the leaders of the Intergovernmental Authority on Development (IGAD) warned they'll "take action" to stop the conflict that the United Nations says has killed more than 1,000 and forced some 121,000 from their homes. The warning came the same day the United Nations said the first of 5,500 additional peacekeepers had arrived in the country. The leaders of the IGAD didn't specify what sort of action would be taken. But a communique issued Friday in Nairobi, Kenya, appears to throw the group's weight behind South Sudanese President Salva Kiir.
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NEW: 72 of 5,500 new peacekeepers have arrived in Juba, the U.N. says
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East African leaders tell South Sudan government, rebels to stop fighting or else
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Group says it will take unspecified action if fighting doesn't stop within four days
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South Sudan's government says it's ready to adopt a cease-fire
The additional personnel will increase the total peacekeeping force in @placeholder to 12,500 soldiers and 1,323 police officers.