Artillery boomed, shaking the ground, as a couple scurried through the streets of Saké, their possessions balanced on their heads, in the embattled east of the Democratic Republic of Congo. At a crossroads, they passed a giant poster of Congo’s president, Felix Tshisekedi, who is standing for re-election on Wednesday. “Our children were born in war. We live in war,” Jean Bahati, his face beaded with sweat, said as he paused for breath. It was the fifth time that he and his wife had been forced to flee, he said.