A PROMINENT group of South African lawyers on Tuesday urged President Thabo Mbeki to extradite Ethiopian former dictator Mengistu Haile Mariam, who is accused of mass murder. The General Council of the Bar, representing 1700 advocates, said that Mengistu, who is wanted for genocide in Ethiopia, could not claim immunity from prosecution and extradition as a former head of state because of the nature of his alleged crimes. The government said it allowed him to come here on humanitarian grounds, for heart treatment from his home in Zimbabwe, but it has since received a formal extradition request from Ethiopia. The council called on Mbeki’s government “to discharge its international duties as regards Ethiopia and to send out a message … that South Africa will not be a haven for international criminals of any sort.” The foreign ministry said it was reviewing Ethiopia’s request.