NEW : Joseph Contreras , U.N. acting spokesman on South Sudan , said , `` It is a very , very fluid situation , so U.N. leader says South Sudan violence shows ` ` some signs '' of spreading . NEW : South Sudan Red Cross reports 19 killed in violence , U.N. says . NEW : U.N. 's Ban Ki - moon urges president to end the violence that has killed people . NEW : South Sudan government must resume dialogue with opposition , Ban says .
NEW : U.N. leader says South Sudan violence shows ` ` some signs '' of spreading . NEW : South Sudan Red Cross reports 19 killed in violence , U.N. says . NEW : U.N. 's Ban Ki - moon urges president to end the violence that has killed people . NEW : South Sudan government must resume dialogue with opposition , Ban says .