A Silicon Valley startup is using drones to deliver medicine and blood to patients in Rwanda, and it plans to expand to other countries by the end of the year. The company, Zipline International, announced this week that it will begin flying its drones in Rwanda in July, under a partnership with the government. The unpiloted autonomous vehicles will ferry supplies to hospitals and health centers across the tiny East African nation, forming what Zipline describes as the world’s first drone delivery system to operate at a national scale.

Rwanda is one of the world’s poorest countries, and infant mortality rates remain high. Deaths from HIV, tuberculosis, and malaria have plummeted over the past decade, as the government invested heavily in its healthcare system, though delivering drugs and medical supplies in the “land of a thousand hills” still poses major problems.

“To put it into perspective, when you don’t have paved roads, sometimes it’s impossible to get out to these hospitals and health clinics, and sometimes it’s just difficult,” Keller Rinaudo, Zipline CEO, said in an interview Monday. “But it’s always unpredictable and unreliable.”