Fighting in Khartoum between Sudan's army and the paramilitary Rapid Support Forces is spreading throughout Sudan. Violence in the western Sudanese region of Darfur threatens to revive the civil war and genocide that engulfed that region 20 years ago. And, there's no May Day parade this year in Cuba due to an acute fuel shortage crisis on the island. Also, pollution from the Tijuana River to the Pacific Ocean have long plagued swimmers and surfers on both sides of the US-Mexico border. We hear about how a recent court settlement is bringing hope for cooperation. Plus, a new book, "Winnie and Nelson: Portrait of a Marriage," explores a fraught political partnership.