The death of George Floyd in Minneapolis has prompted the biggest protests about race and police brutality in America for 50 years. Around the world, thousands of people have joined marches against racism. Reporter Clive Myrie asks if this could be a moment that changes race relations in America for good. He hears from protesters, eyewitnesses and former police officers about why this killing has had such a powerful impact, and speaks to people from black and white communities in Minneapolis about their hopes and fears for the future.