Sudan’s government has declared a state of emergency in West Darfur state after at least 40 people were killed and 58 injured in three days of tribal clashes, the latest incident in a resurgence of violence in the Darfur region since the signing of a peace agreement late last year and the withdrawal of UN peacekeepers. Residents of the city and an internal UN security bulletin quoted by the Reuters news agency reported the use of heavy weaponry and rocket-propelled grenades, with pictures and videos from residents showing plumes of smoke rising from the city’s neighbourhoods.