Warning: This report contains violent content. Two years after civil war erupted in Sudan, the country is facing what aid agencies call the world's worst humanitarian crisis. At a summit in London, Foreign Secretary David Lammy addressed diplomats and aid officials, urging continued support. He called it "morally wrong" to abandon a nation where at least 20,000 have been killed, and 25 million people are at risk of famine and extreme hunger. Read more: https://news.sky.com/story/how-brutal-