Officials in Nigeria Saturday said 31 people were killed and several others were injured in bombings in the city of Jos. At least five explosions occurred in two commercial districts of the city, setting a number of parked cars on fire, UPI reported. An aide to the governor of Plateau state told CNN two bombs exploded in the Angwa Rukuba area and three more occurred in nearby Kabong. There was no immediate claim of credit for the bombings and no arrests were reported. Troops moved in to secure the areas and fired shots into the air to disperse angry crowds, CNN said.