A Congolese riot-police officer restrains a supporter of Congolese opposition leader Etienne Tshisekedi outside the candidate's headquarters in Kinshasa, Congo, on Thursday. (Associated Press)

A Congolese riot-police officer restrains a supporter of Congolese opposition leader Etienne Tshisekedi outside the candidate's headquarters in Kinshasa, Congo, on Thursday. (Associated Press)