Gunmen killed nine people and injured two in a shooting spree in the Nigerian town of Obrikom and the nearby village of Obor, in oil-producing Rivers state, on Friday evening, a police spokesman and witnesses said on Saturday. 'It was at about 7:30 p.m. yesterday. Some unknown armed men invaded the Obrikom and Obor communities ... killing nine, injuring two persons,' a Rivers state police spokesman Ahmad Mohammad said. He said the house of a parliamentary opposition candidate, Vincent Ogbagu of the All Progressives Congress, was set on fire. APC presidential candidate Muhammadu Buhari beat incumbent Goodluck Jonathan in a landslide victory last weekend, creating a bitter mood in Jonathan's home region.