The truce, the sixth since October 2012, was announced by the leadership of the Marxist guerilla group earlier this month.
Rebels say they've started a "definitive path toward peace" that is being hailed as a turning point in the region's longest-standing leftist insurgency.
Hopes of a cessation in fighting crumble as both rebels and Kiev-backed forces resume shelling around the embattled air space.
Kiev and pro-Russian rebels have agreed "in principle" to a new ceasefire agreement in the separatist-held Luhansk region.
Al Qaeda-linked militants have claimed responsibility for an attack that targeted a compound near the US embassy in Yemen's capital.
A rebel leader said prisoners of war would be transferred to Kiev on Saturday night.
El Salvador's government has said it can no longer provide “exclusive” prison facilities for the notorious MS 13 and Barrio 18 gangs.