Nigerian President Muhammadu Buhari has won a second term at the helm of Africa’s most populous state and top oil producer, the electoral commission chairman said on Wednesday. The statement followed an election marred by delays, logistical glitches and violence, Reuters reports. Buhari took 56 percent of votes against 41 for his main rival, businessman and former Vice President Atiku Abubakar of the People’s Democratic Party (PDP). Hours after Buhari was declared the victor, Abubakar rejected the results of the “sham election” and vowed to challenge it in court.