A leading rights group said on Thursday that attacks by Sudanese paramilitary forces and their allied militias, which killed thousands in the western region of Darfur last year, constituted a campaign of ethnic cleansing against the area’s non-Arab population . The paramilitary Rapid Support Forces, which has been fighting Sudan’s military for over a year, allied with armed militias to carry out attacks against the ethnic Masalit and other non-Arab groups in El Geneina, the capital city of West Darfur state, Human Rights Watch said in a new report. Sudan has been rocked by violence since mid-A…