The National Guard has been deployed to the US city of Minneapolis during a third straight night of unrest. Angry protests have spilled over into violence and looting. They come in response to the death of an unarmed black man in police custody earlier this week. The city’s mayor has called for criminal charges to be filed against the officer who was filmed kneeling on George Floyd’s neck during his arrest. The US Department of Justice has launched an investigation into Floyd’s killing, which protesters say was fueled by racism.