Residents of Sudan's besieged city of al-Fashir have been taking refuge in underground bunkers to try to protect themselves from drones and shells after intensifying attacks on displacement shelters, clinics and mosques. Famine-stricken al-Fashir is the Sudanese army's last holdout in the vast, western region of Darfur as it battles the paramilitary Rapid Support Forces (RSF) in a civil war that has raged for two-and-a-half years. The conflict, which erupted from an internal power struggle, has triggered ethnic killings, drawn in foreign powers and created a massive humanitarian crisis. The army has been gaining ground elsewhere in Sudan, but Darfur is the RSF's stronghold where it aims to base a parallel government, potentially cementing a geographical splintering of the country....