Protests have broken out in the Senegalese capital Dakar and in the southern city of Mbour over continuing power shortages. In Dakar, several government buildings were set on fire including the offices of the state electricity firm, Senelec. Security forces in Mbour fired tear gas to disperse thousands of demonstrators. The trouble over power cuts, which have lasted 48 hours in some areas, come just a week after rioting against the president.